How to Test Glow Plugs From Start to Finish (With a Multimeter) - The Complete Guide.
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- เผยแพร่เมื่อ 26 ก.ย. 2024
- This is for glow plugs without a pressure sensor...
My diesel Won't start? There's white smoke coming from the exhaust... It starts OK when the engine is warm?
For more information, see: do-it-up.com/v...
Other Videos:
- Without a test meter: • How to Test Glow Plugs...
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Glow Plugs - (USA) - ebay.us/8MSxEU
Test Meter (Multimeter) - (UK) - ebay.us/TYvuAn
Multimeter (Test Meter) - (USA) - ebay.us/5UXl14
Glow Plug Removal Tools - (UK) - ebay.us/XCVgft
Glow Plug Removal Tools - (USA) - ebay.us/FohVav
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Jumper Cables - (USA) - ebay.us/92CL4z
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There is a typo at 5:57 where it says 3m ohms, this should be 3M ohms...
- How to Fix?
Petrol engines start with the assistance of a spark from a spark plug to ignite the fuel. Whereas diesels start using the compression of the fuel mixture. However, diesels don’t like starting when cold. Hence diesel engines are fitted with glow plugs that heat the air fuel mix to aid starting when cold.
If a diesel engine is running well and starts easily when the engine is warm, but won’t start when cold, (or takes ages to get it started when cold). It could be an issue with the glow plugs, the glow plug system (glow plug module, relay, or voltage supply).
Diesel Cold Starting - Fault Symptoms
The engine turns over at a reasonable speed (it’s not slow cranking), but the engine won’t start?
The engine starts, but only after some time (and multiple attempts)?
White smoke is seen from the exhaust (unburnt fuel).
When the engine is warm, it starts easily.
You may see white smoke from the exhaust whilst trying to start the engine and for a short while when the engine starts (unburnt fuel).
Diesel Cold Starting - The Causes
If you see white smoke coming from the exhaust (unburnt fuel), after several starting attempts…
Some, or all of the glow plugs may have failed?
There maybe no voltage supplied to the glow plugs?
The glow plugs may switch off too soon. The timer (or control module) could be defective?
Diesel Cold Starting - Things to Check
The glow plug relay:
The glow plug timer (or control module):
The glow plugs:
Note:
The glow plug relay is sometimes a separate item, but it can also be incorporated inside the glow plug module?
With a Multimeter, we can measure:
The Supply Voltage:
The Timer (Control Module):
The Resistance (and Continuity):
What Should I Check First (three easy steps)?
For the initial testing, you will need a voltmeter, or a simple method of checking for a voltage. However, it’s not essential. If you don’t have a voltmeter, just go straight to the section on Testing Glow Plugs Without a Voltmeter (Multimeter)…
Is there a voltage at the glow plugs?
How long is the voltage applied to the glow plugs?
Check the glow plugs?
1. Is there a voltage at the glow plugs?
If there is a voltage supply to the glow plugs, then we know the glow plug relay and glow plug control module are probably working (also see 2. below).
2. How long is the voltage applied to the glow plugs?
There is a timer that applies a voltage to the glow plugs for a set amount of time. Therefore you need to check how long the supply to the glow plugs is switched on.
3. Check the glow plugs?
If the correct voltage is applied at the glow plugs (and for the correct amount of time), then the glow plugs will need to be checked.
Please refer to the vehicle manual, as each vehicle may be slightly different.
Additional Notes:
The next generation of glow plugs may have a different supply voltage to that of the battery. The voltage may be pulsed and have a variable timer (the duration of supply controlled by the vehicles control unit and the requirements of the engine). Typical values (next gen) 4.4v to 7v. The resistance value may also be below 1 ohms. You may need to refer to the manufacturers specifications, to get the correct value…
A DC clamp meter can be used to measure the current. Take care when placing the clamp meter, as you can measure the current of other items in the circuit.
7:25 I would recommend to everyone before you start removing the glow plugs blow out the surrounding area of the glow plugs with compressed air to prevent and dirt, grit or grim from entering the cylinder or cylinder head threads when installing the new glow plugs.
Great tip, just make sure you wear some safety specs before blowing any debris out... 😀
yes, definitely, and plug the holes with something too if possible in case anything falls/gets dropped down the glow plug holes
@@doitup lol yes
Dude, you deserve a big round of applause for this educational video in the style of Do-It-Yourself at Home....Thank you very much and God bless you
Hi, thanks for letting me know it helped you out. It's much appreciated... 😃
Very clear and simple to understand. I came looking on TH-cam as my truck is struggling to start in the current extreme cold weather in UK. Best glow plug issue video I seen today.
Hi, thanks for your comments. It's great to know you found it useful and that it helped you out... 😃
Thanx for this Video.
A Tip from me:
please pay attention! There is a difference in the operating voltage of the glow plugs in the car.
There are 5 volt and 12 volt glow plugs.
The difference can be seen in the color of the insulator between tip + and thread -.
Yellow or orange insulator are 5 volt glow plugs.
Black insulator are 12 volt glow plugs.
The voltage for 5 volt glow plugs is regulated by the control unit.
Hi, thanks for the great tip. It's a very valid point. Just to expand on voltages a bit, (just looked at the NGK catalogue to see the actual range of voltages). There is a large number of different glow plug voltage specifications for vehicles, ranging from 4.4v all the way up to 23v. The majority appear to be rated at 11v. However, it should be noted that the 11v glow plug will work perfectly fine on 12v, which is the case in the video. I guess they're rated at 11v, in case the output from the vehicle's electrical system is low. Plus they will have a + or - operating tolerance, (which isn't quoted). As you say, the 5v glow plugs will be used on a 6v system, or the voltage will be regulated down to 5v by the control unit. 23v glow plugs will no doubt used on a 24v system.
I didn't realise there was a colour coding system. However, I would only use a colour indicator as a guide (past experience, where manufacturer's don't strictly adhere to helpful indicators). The thing to take away from this is, always check your part numbers on the manufacturers website to ensure the correct part is being ordered and fitted. If your vehicle system is 12v and you find 5v at the glow plug (and you don't have a manual). Check the glow plug specifications on the manufacturers website, to check the voltage is correct. 😃
Another basic test is you use a 12v tester with a bulb, put the clip of light tester to battery positive and touch each glow plug, it's a loaded test so if the plug is good the test light should light up, if not, it's defective, don't use an led light tester. You can make a light tester with a headlight bulb and wire if you have no tools. Great video
Hi, that's a great tip, and well explained. That should help anyone who doesn't have a test meter, or needs another test to confirm a defective glow plug... Thanks for sharing... 😃
Thanks for taking the time to share this. Super helpful and informative.
Hi, Thanks for letting me know. It's much appreciated... 😃
Wonderful, thanks a lot. Next video suggestion: How to remove, clean the bores and reseat injectors. This little Corsa seems to be in dire need of this.
It certainly was... It took me about 5 days to extract one injector. I had to keep walking away in despair and coming back to it. I even made a bespoke tool to jack the injector out, but would it budge... Perseverance got the injector out in the end. Moral of the storey... Always clean the seats and use new copper washers on replacing the injectors. Don't go, "oh, they look pretty good" and put them back as they were... 😕 You were spot on. Thanks for your reply, it's much appreciated... 😄👍
Very clear and helpful. Many thanks
Hi, no problem. Glad it helped you out. Thanks for letting me know... 😀
Superb video, straight forward and easy to follow this tutorial, thank you.
No problem... Thanks for your positive comment... 😃
Good video 👍. One error: GP #1, U wrote 3 milli ohm instead of Mega. Add a note that new gen glow plugs would have a 4.4V or 7V supply. Short test leads to check the residual resistance which can be deducted from the GP measured resistance. One more point is that the current can be measured w/ a DC clamp meter @ battery terminal for all 4 (will include ECU & Acc) or on each glow plug wire.
Hi, yep, it should have been an 'M' rather than an 'm'. Unfortunately, once the video is uploaded, you can't change it easily (I've updated the sub titles). I've added some notes on the other info into the description. Thanks for the great info... 😃
You can check them quickly and easily before even removing them with just the spanner to undo the nut holding the wire
Hi, yes, you're quite right. See the video here... Measure the Resistance (Still Fitted... th-cam.com/video/_bxblpUIXpg/w-d-xo.html. It should be noted that the resistance values of the glow plugs (when fitted), can be different to when they are measured (removed). This is because of the potential for additional resistance when measuring, (say between the tip of the glow plug and an earth point elsewhere).
Measuring the resistance (when fitted) should still give a good indication if a glow plug is any good, but there may be occasions when it could give the wrong result? I.e. If a test shows the glow plug as OK, it should be fine. However if it shows bad, it's worth checking when the glow plug is removed just to make sure...
There is a table of results here: th-cam.com/video/nFrvzstFqwE/w-d-xo.html that gives an illustration of the different results, (when fitted and removed). Thanks for your comment, it's great to have extra info that can help others... 😃
Just remove the feed wire, activate the feed, tap the wire on the plug, if it draws with a spark it's good, no need for a multi meter or removal. Takes seconds if plugs accessible
Hi, great tip. Thanks for the extra info... Nice and easy... 😃👍
Hi all. Many many thanks. Super lesson. Much appreciated.
Hi, no problem. I'm glad it was of use... If you need more info, you can find it here: do-it-up.com/vehicles/engine-transmission/diesel-wont-start-when-cold-how-to-fix-glow-plugs/ I sometimes add this link to a reply, as once the video is uploaded, I can't update it without creating another video. So I add any updates and extra info to the web page... Thanks for letting me know that you found the info useful. It's always great to hear it helped someone out... 😃
Best self help video iv ever seen top job thanks very much 👍
Hi, thanks for your comment, it's much appreciated... 😀👍
Absolutely brilliant! So informative, and clear instructions. Thank you for posting this. Very professional and extremely helpful. 12:08
Hi, thanks for your comment. It took a while to make the video, so it's much appreciated... 😃
Really, really good video.👍👍
Very clear, logical and easy to follow.👌
Well done.
Thanks for making the video and for taking the time to upload. 🍻
Hi, thanks for your comments. It's much appreciated and makes the effort worthwhile... 😁
PV = n R T
Hi, on first glance this looks completely wrong and could have been auto directed into the offensive spam box! Definitely a bit of gas, pressure, volume. And with a bit of help from the glow plugs... Temperature. Spot on... 😁
Simple and valuable ❤
Hi, thanks for letting me know, it's much appreciated... 😃
Cant be more clear and easy :) Thank you ;)
Hi, thanks for letting me know. It's much appreciated... 😃
thanks this was just what i needed nice and clear and easy to follow great job!!!
Glad it helped! 😃
Thank you for making the video, very well explained and filmed.
Hi, thank you. I'm just an old fart with a pocket camera and a cheap tripod, so it's much appreciated... 😄
Świetny filmik, bardzo mi nim pomogłeś za co szczerze dziękuję.
Cześć, nie ma problemu. Cieszę się, że ci to pomogło. Dzięki za informację, bardzo to doceniam... 😃👍
@@doitupSpoczko
Cheers
Incredible great video. Thanks bro. I measured my plugs and third of four are fail.. I don't have tork device. So I thigntened them normally.
Hi, if you don't have a torque wrench, then it's not a huge issue as long as you use the torque value as a guide. It's basically there to stop you breaking the glow plugs, stripping the threads, or to ensure you can get them out again the next time (without breaking). Yorumun için teşekkürler. Birine yardım ettiğini bilmek her zaman harikadır... (Thanks for your comment. It's always great to know it helped someone out...) 😃
This can only be a german guy! Very detailed :) thanks!
Kein Problem ... Aber du machst mir jetzt ein wenig Sorgen ... Ich dachte, meine zwölf Zehen bedeuten, dass ich Cornish bin? 😃
Thank you. Greatly appreciated.
Hi, I'm glad it helped you out. Thanks for letting me know... 😃
Very informative. Thanks
Glad it was helpful! 😃
Fantastic presentation and explanation!
Hi, I'm glad it helped you out. Thanks for your comments, it's much appreciated... 😃
Learned a lot from this video, cheers
That's great. Thanks for letting me know... 😃
Slight correction. The glow plug does not preheat the chamber, it is too small to do that. The glow plug acts like an ignition source much like a temporary spark plug except instead of a spark like from a spark plug the tip of the glow plug heats up red to white hot which is enough to get the diesel to ignite. That is why the ends of bad glow plugs can look burnt or bubbly when you take them out. The heating element dies which is the major cause of a failed glow plug. Also why you have to heat the glow plugs up several times sometimes when it is real cold. The cold chamber cools off the glow plug too fast.
Some manufactures design the glow plugs to heat at a lower voltage such as 9-10 volts instead of the supplied 12 volts plus. That makes them heat up faster buy supplying more voltage than they are rated at. The down side is that because they are being over driven voltage wise they burn out faster.
Depending on the design the tips of glow plugs can swell or actually break off. Both are a problem when removing dead glow plugs. Plugs that are hard to remove once the plug has been un-threaded some should be lubricated and twisted out slowly with as little outward pressure as possible. If the tip breaks off generally the head has to come off to remove the broken parts, not a great outcome for a "simple" job. Otherwise the tip will bounce around damaging the piston, rings, and valves.
Hi, thank you for taking the time to comment. This is such great information and is explained so well... Any information that helps others is always appreciated. Thank you... 😄
Lose the music
@@timothysmith7436 music was great , no other sounds was needed to hear
Great video, and great editing, thanks!
Hi, thanks for letting me know. It takes a while to make these videos, so your comments are much appreciated... 😃
very good presentation.
Hi, thanks. It took a lot of editing to make, so it's appreciated... 😃
Great video. I am going to check mine glow plugs. Car has 220 000 km and hardly starts in -3 C outside.
Hi, thanks. It takes a while to make a video, so it's great when someone lets you know it helped them out. Hope you get it fixed soon... 😃
Thank you so much
No problem, it's always good to hear it helped someone out. Thanks for letting me know... 😀
awesome! better than other similar videos
Hi, thanks for your comment, it's much appreciated. It makes the time and effort all worthwhile... 😃
Great video of my exact van so very helpful to me. I've just resealed my hight pressure pump to cure a leak and bad starting but the pump kit did not cure my bad starting.but when running engine after pump refit I notice like your engine it had a bad injector seals so just done them but while doing injector seals thought would check glowers and I've got 2 good and 2 bad.
Thanks for vid keep me coming
Hi, yes... You spotted my bad injector seal. It took my 5 days to get the injectors out. In the end I had to walk away and come back the next day to try... and try again, (I was so frustrated with them not coming out). Lesson learnt, don't leave the injector seals until later! Glad the video helped you out. Makes the time and effort it took to make video all worthwhile... 😃
@@doitup no mate all worth while keep doing the vids. Thing is you can't turn the injectors cos of the clamps.thanks andy
When testing the supply voltage, how to connect the 2 cables of the multimeter? Or just using the red/positive one? Thx.
Hi, unfortunately I missed this bit (oops!)... The negative lead (often black) can go on the negative (-ve) of the battery connection, or anywhere where there is bare metal work on the vehicle (also sometimes called an earth on vehicles). The bare metal work must be un-insulated and be connected back to the negative side of the battery through the car bodywork (as long as it's not a fiberglass vehicle where a negative cable has to be run back to the battery). There are often earth points on the vehicle's bodywork for connecting any negative leads (usually black) for connection back to the battery, (the vehicles metal body acts as a cable to the battery).
For info... Earth and negative can be very confusing terms on vehicles, as they are often the same thing. However, you would never connect a negative lead to earth on household electrics, as this would cause the circuit breaker to trip, or the fuse to blow. So, vehicle electrical naming conventions (and practices), can be different to general electrical naming conventions (in some cases). It doesn't make it easy...
Hope this long winded reply is a useful explanation and helps... 😃
@@doitup thx for the detailed response.
That's what I did, connected the negative to the battery.
That's great, you can't go wrong doing that... 😃
Awesomely informative, good work!
Great, thanks for letting me know. Makes all the effort to produce it worthwhile... 😃
Machanics should make videos like this guy 👍👍👍
Hi, thank you. Much appreciated. Makes the time and effort all worthwhile... 😃
Very useful information thank you so much for you
No problem. I'm glad you found it useful. Thank you for letting me know... 😃
Your advice was very helpful.
Glad it was helpful for you. Thanks for letting me know... 😃
Awesome 👏, i feel like I know it all thanks to you
Hi, thanks for your comments. I'm sure I must have missed a few things! There's some more detail here if you need it: do-it-up.com/vehicles/engine-transmission/diesel-wont-start-when-cold-how-to-fix-glow-plugs/. Hope you get it fixed soon... 😃
Brilliant video, thanks for making it easy, Glow plugs for Dummies (that's me BTW)
Hi, thanks for letting me know. It's much appreciated... 😃
best video i ever watch well done great job!
Wow, thank you! I'm sure a better one will come along... 😀
Thanks very clear and precise
Glad it was helpful! Thanks for letting me know, it's great when it helps people out... 😀
Great video! Very useful, just suggest wd40 few days before and compressed air to clean before removing!
Hi, yes... Great tip. WD-40 and blowing out any debris would certainly help. Don't forget your safety specs though. Thanks for your comment... 😃
Thanks bro that was super helpful 👍
That's great, thanks for letting me know... 😃
Excellent tutorial thanks for posting
No problem, thanks for letting me know... 😃
Excellent video thank you
No, no, no... Thank you. I hope it was useful... 😃
Really good video 👍👍👍👍👍👍
Hi, thank you. It's very much appreciated... 😃
This is a bloody good video 👍
Thanks, glad you liked it... 😃
You didnt show where you put the negative, is it to the neg terminal of the battery?
Hi, unfortunately I missed this bit... The negative lead (black) can go on the negative (-ve) of the battery connection, or anywhere where there is bare metal work on the vehicle (often called earth). The bare metal work must be un-insulated and be connected back to the negative side of the battery through the car bodywork (as long as it's not a fiberglass vehicle where a negative cable has to be run back to the battery). There are often earth points on the vehicle's bodywork for connecting any negative leads (usually black) for connection back to the battery, (the vehicle body acts as a cable to the battery).
For info... Earth and negative can be very confusing terms on vehicles, as they are often the same thing. However, you would never connect a negative lead to earth on household electrics, as this would cause the circuit breaker to trip, or the fuse to blow. So, vehicle electrical naming conventions (and practices), can be different to general electrical naming conventions (in some cases). It doesn't make it easy...
Hope this long winded reply is a useful explanation and helps... 😃
@doitup wow really appreciate that bud. 🙏
No probs... 👍😀
Cracking video, thank you.
Hi, no problem. Thank you for your comment. It's much appreciated... 😃
Awesome video👌👍👊
Hi, thanks for letting me know, it's much appreciated... 😄
Great video! Very methodical approach.
You have a very nice multimeter, now go ahead and treat yourself to a new pair of disposable gloves 😂
Hi, your comment gave me a good laugh! Good spot... I hate waste (which doesn't do my waist line any good either). I have a box of these and have to keep extras in my pocket, as they keep ripping! I end up trying to make these last as long as I can and then change them. Only two more boxes to go and then I'll get some better ones..! Thanks for your comment and for making me smile this morning... 😄
Glow plug removal is easier if the engine has been warmed up.
Hi yes, nothing better than a bit of heat expansion to loosen things up... 😃👍
Super method of testing and very understandable.
Thank you
जय हिंद
Hi, Thanks for letting me know. Hope you get it fixed soon... और दुनिया के सभी स्वतंत्रता प्रेमी देश 😃
Great video! Thanks!
Hi, thanks for letting me know. It's much appreciated... 😃
Great explanation... 👍🏾
Thanks for letting me know, it's much appreciated... 😃
Great easy to follow instructions thank you, at the end of the video is a puff of smoke injector area is that a bad injector seal?
Yes, I think it is. I did wonder if anyone would spot that! 😀 The injectors have new copper washers fitted now, so no longer an issue. However, it was a pain getting the injectors out (because of the carbon build up around the injectors). So, two schools of thought... If it ain't broken leave it. Or, fix it as soon as you see it. In the end, the injectors had to come out for another job! All I can say is; always fit new copper washers when removing injectors. It saves a whole load of grief later on..! Thank you for your positive comments... 😄
@@doitup yeah I hear they are a pig of a job to do! And your right they are one time use copper crush washes I believe so best to use new ones. The reason I pointed out was it would of made another great video👍
@@z0m123 you can anneal them one more time if you dont have new ones
Excellent job, please what is the correct resistance that should be in the Glow plugs
Hi, the typical resistance value should be approximately 1 to 6 ohms. However...
- Newer vehicles may have a low resistance value. If you know the glow plug manufacturer, try and check the glow plug data sheet for your vehicle, to get the actual value.
- It's always worth checking your test meter for its resistance value, before measuring anything. There's instructions on how to do it here: do-it-up.com/vehicles/engine-transmission/diesel-wont-start-when-cold-how-to-fix-glow-plugs/#Checking-the-Glow-Plug-Resistance, see 3.1.
- There is a table of typical resistance values here: do-it-up.com/vehicles/engine-transmission/diesel-wont-start-when-cold-how-to-fix-glow-plugs/#Typical-Glow-Plug-Resistance-Values. This shows typical resistance values for new and defective glow plugs.
Hope this helps... 😃👍
Where is the negative connected to during the voltage testing?
Hi yes, I did omit to say where to put the earth/negative lead in the voltage testing section, (but did include it in the next section th-cam.com/video/nFrvzstFqwE/w-d-xo.html, Oops..!). Basically, if the vehicle uses the bodywork as the -ve (negative) return path, you can use anywhere where there is uninsulated bare metalwork, an earth point, or the battery negative should be fine (-ve earth vehicles). You always need to make sure there is a good connection, even if it looks reasonable, as there could be a thin film of dirt or grease on there. If the vehicle has a fibreglass body, you have to find an earth return connection (wire) back to the battery, (or the battery), as the fibreglass body cannot be used as a return path... Hope this helps... 😃
@@doitup after all this time you actually replied....you're goated man
No probs, it takes awhile to catch up sometimes... 👍
thank you. so much dear its help me alot
Thanks for letting me know. I'm glad it helped you.. 😃
Wow. It's a really good and calm video that just saved me time and money!
Love it!
Hi, thanks for your comment. It's much appreciated... 😃
Thanks!
No problem, I'm glad it was of use... Thanks for letting me know... 😃
Think you need to do them injector seals too
Yep, you're spot on. It took me about 5 days to get all the injectors out! Kept having to walk away and come back to them... It was a good lesson in changing the copper washers as soon as you can, or every time you take the injectors out... 😃
Nie szczelny Injektor na 2 cylindrze chyba. A tak poza tym super video!
Cześć. Zauważyłeś złą (miedzianą) uszczelkę na jednym wtryskiwaczu. Zajęło mi 5 dni, żeby wyjąć wtryskiwacze z powodu nagromadzonego węgla. W końcu musiałem odejść i wrócić następnego dnia, żeby spróbować... i spróbować jeszcze raz (byłem tak sfrustrowany). Nauczka, nie zostawiaj uszczelek wtryskiwaczy na później! Cieszę się, że filmik ci pomógł. Sprawia, że czas i wysiłek włożony w nagranie filmiku są tego warte... 😃
@doitup Witam witam! właściwie to tę podkładkę miałem na myśli. Kiedykolwiek musiałem wymontowywać wtryskiwacze, montując starałem się je wymienić na nowe. Bo niestety później może być taki efekt, że nie będzie szczelna. Pozdrawiam z Austrii.
Niestety, przekonałem się na własnej skórze i powinienem był wymienić je za pierwszym razem, ale myślałem, że wyglądają dobrze... Pozdrowienia z Kornwalii, Anglia. 😀
i measured new Bosch 5V showing 8 ohms
Hi, the 5v may well be correct. Bosch do a range of glow plugs that run at either 11v, 5v and 7v dependant on the vehicle and glow plug fitted. You will need to check the specifications to see what it should be? The resistance doesn't sound right, so you need to check your test meter reads 0 ohms before measuring. If it doesn't read 0 ohms, you can still measure the resistance, by doing this...
Select ohms, and connect the multimeters leads together. Is the meter reading 0 ohms? If not, recalibrate your test meter. If there is no facility to do this, just subtract the reading you obtained (when connecting the leads together) from the actual reading taken from the glow plugs.
For example. If you get a glow plug reading of 14 ohms and your multimeter had a reading of 8 ohms, we now know the glow plug measured 6 ohms (14 ohms - 8 ohms = 6 ohms).
Make sure the contact points (where you measure the glow plugs) are clean and free from oil and corrosion.
For Bosch:
Resistance ∞ Ω: malfunction: defective glow plug.
Resistance < 0.2 Ω: malfunction: defective glow plug.
Resistance > 0.2 Ω and < 5 Ω: glow plug OK.
Let us know how you get on, as it may help others. Hope this helps and you get it fixed soon... 😃
Best one ❤❤❤❤
Hi, thanks for letting me know, it's much appreciated... 😀
great vid
Hi, thanks for letting me know, it's much appreciated... 😃
Great content!!!
Hi, thanks for letting me know. Much appreciated... 😃
Excepent video !!! Well done😄
Hi, thank you. Your comments much appreciated... 😃
Good video.
Glad you found it useful. Thanks for letting me know... 😃
Very useful , thanks
Glad it was helpful! Thanks for letting me know... 😃
@@doitup your other video with testing the plugs with wires is good too . I'm about to try it out .
That's great, thank you. I hope you find the issue and get it sorted soon... 😀
Mais bem explicado é impossível
Olá, obrigado pelo seu comentário, é muito apreciado... 😃
Those tests can tell if the sensor pressure working?
Hi, I've not tested any glow plugs with pressure sensors, so wouldn't be able to advise. It looks like they have electronics built into the head of the glow plug and a diaphragm with a piezo-resistive sensor to measure the pressure. Any movement of the diaphragm will change the resistance of the piezo-resistive sensor, which will be measured by the electronics and fed back to a control unit. This probably means the only way you can test the glow plug electronics, is by plugging the vehicle into a computer to measure the glow plug parameters.
Searching the internet, it looks like you can check the resistance of the glow plug heating element using a test meter (steering clear of the glow plugs electronics)? There is also a suggestion these type of glow plugs work using higher voltages? Therefore, before you do anything, I would check the glow plug manufacturer's website for more information, as they sometimes provide data sheets.
As usual, at your own risk. I hope this helps in some way... 🤔
Firstly, that engine starting system has an issue, its cranking to slowly. Secondly, I always used an amp meter to test glow plugs, not an ohm meter, etc.
Hi, thanks for your comments. I can't agree with you on the first point I'm afraid. I admit it doesn't turn over that fast, but the slow cranking is probably down to the remaining power left in the battery (from the number of times the engine has been turned over in trying to start). Plus once the glow plugs were replaced, it would always start...
I agree with you on the second point, measuring the current is always a good thing to do. I.e. A vehicle battery may show 12v when measured, but it doesn't mean it has any guts (power) behind it. A clamp meter is always good tool to use when measuring the current flow (for a vehicle battery a discharge, load or drop tester). Many people have a basic test meter that can easily measure the voltage and resistance. Unless you're familiar with measuring current, it's all too easy to blow your test meter if it's connected up the wrong way...
Generally it's easy to measure the voltage supplied and the actual resistance of glow plugs. Many of the manufacturers supply the data for these measurements. So you can easily check if your glow plugs, or the voltage supplied is out of specification. Hence the video showing these methods. Hope this helps... 😃
@@doitup my whole career, now retired, was working on mercedes vehicles. So I have an insane amount of experiance with diesels. This is just to let you know I'm not some joe shmo out there with no real experiance, not for bragging reasons. So, regarding glow plugs, both coil and later pencil types, I soon found early in my career back in the early 70s that testing by using an ohm meter as per instructions by mb showed that gp were good and yet we had issues and many times comebacks. The ohm meter can show good but that just shows a connection not under load. So I decided I wanted to test them under load. So wanting to find the bad gp, I would test them in situ. I would disconnect the wires to them or go to the plug to them and use the pins at the plug to the gp and then using a simple stand alone amp meter, I would put one lead on the plus side of the battery and then use the negative side of the meter to touch each gp post. If good the meter would go to about 20 amps and hold for a second. If it held it was good. If the meter started to go up and then drop I knew I had a bad gp. That glow plug would have shown good if it was tested by an ohm meter. I did experiments and this proved correct over and over. As we were normally working on 5 cyl engines, if 3 were bad we replaced them all. Anyway, that's my take on it. One other piece of knowledge, depending on the engine you work on, this may not apply. But if you keep getting the same gp going out then that indicates a bad injector. It not spraying, it just squirting streams and not atomizing. Hope this helps. If not, disregard.
Hi, I wasn't after winding you up. I was just trying to point out that many people are unfamiliar, or have never used a test meter before. All the information from the manufacturers points to measuring the resistance and the voltage supply. You can use that information to check against what you have fitted. It's a fairly straightforward process and it's what most manufacturers suggest to do in their documentation which is available online. It's a good indicator...
What you have suggested (in your second reply) is a great explanation and an absolute gem. It comes from years of experience and is a far better test to find faults when glow plugs are breaking down under load. Thank you for supplying the information. It should certainly help others... 😃
This has happend to my Ford Mondeo, yesterday was -20° C. Time to replace them (180k)
Hi, glad you found a solution. Hopefully they're not too expensive, and you can get them out easily... 😃👍
Thanks for feedback! They are about 10 eur each, so fine but I do not feel confident in this weather to do it. I have ordered in car service and I am afraid that I break them, that would be terrible service! All the best and thanks for great guide.@@doitup
No problem, sounds like you'll have it all sorted soon...
What time should it be for glow plugs warm up and what number of omhs would be correct?
Hi, the warm up time can vary depending on the vehicle and its design... Generally, it should be around 10 to 20 seconds. Some fancy modern electronics, may vary the warm up time in some cases?
Resistance - For a standard glow plug, the resistance should be 1 to 6 ohms. There is an illustration of resistance values here: th-cam.com/video/nFrvzstFqwE/w-d-xo.html. However, the values may be more specific for some glow plugs and more modern vehicles. If you know the make and reference number of the glow plug, you can sometimes look up the specific details on the manufacturers website.
It should also be noted that the voltage to the actual glow plugs may be different in more modern vehicles, (not 12 volts). So it may be worth looking this up on the manufacturers website if you can... Hope this helps... 😃
Brilliant thanks 😁
Hi, No problem 👍 Thanks for letting me know... 😃
perfect,thanks
Glad it was helpful, thanks for letting me know... 😃
thank you
No problem, hopefully you can get any issues sorted soon... 😃
Saying the Ohm reading indicates a bad glow plug is not enough. W also need to know what the proper resistance will read if the glow plug is good. I've watched several similar videos, and all omit that information.
Hi, please see the video at... 6:36, 9:49, 10:04, 11:16 & 11:27 where it shows new glow plugs being tested and provides resistance measurements for new glow plugs. There should be a low resistance so heat is generated, but not a dead short. Hope this helps... 😄
you werent paying attention, it was very clear, typically, when buying new glow plugs, the resistance values are printed on the box
Hi, thanks for the info... It's a great tip. 👍 Also look out for the torque values, they may be on the box as well. 😃
👍. What is the puff of smoke from fuel injector 2?
Hi, well spotted! The injector copper washer is not sealing properly... I ignored this at my peril. I needed to remove the injectors some months later. It took 5 days (of going away in despair, and coming back to try again) before I got them (it) out! Carbon deposits had formed around the injector fixing it in solidly in place. Moral of the story:
1 - If you take the injectors out, always clean and replace the copper washers.
2 - See a puff of smoke, replace the copper washers at the earliest opportunity.
3 - Walk away and hope you never have to take the injectors out!
4 - Wish you'd done something different!
In my case the following order applied... 1, 3... then 4.
You live and lean..! 😥
What means when voltage doesnt hold 22 sec when I checked for ,but just 2 sec. max.Its a glow plug relay problem?Thank You
Hi, it sounds like it maybe a glow plug timer (relay) issue. However, how long the glow plugs are activated for will be dependent of the vehicles design (and its age). I.e. A more modern vehicle may have an intelligent system where the glow plugs are activated, dependent on a number of parameters (cylinder, air, fuel temperature, etc). Unfortunately, you can't say for certain unless you know the specific design parameters for that vehicle. If you can't find anything else wrong, all you can do is swap out the unit, or run a temporary supply to prove the system. Hope this helps in some way... 🙂
I've changed 5 of 6 glow plugs number 2 was hard to undo it's now loosened off but just keeps spinning it will lift up a few mm with pliers but won't come out I'm pretty sure its not snapped do you have any tips for this issue.The rest came out easily.
Hi, Sounds like the thread has stripped on either the glow plug or cylinder head. Unfortunately, the glow plug has to come out, but the thread in the head may get damaged in the process, (if not already damaged). Luckily, there are plenty of kits on eBay for repairing the cylinder head if the thread is stripped. Here are some examples: www.ebay.co.uk/sch/i.html?_from=R40&_nkw=Glow+Plug+Thread+Repair&_sacat=0&LH_TitleDesc=0&_sop=15&mkcid=1&mkrid=710-53481-19255-0&siteid=3&campid=5338823856&customid=UKThreadRepair&toolid=10001&mkevt=1.
First off apply some lubricant and let it soak. Try and unscrew the glow plug carefully whilst applying upward pressure, using mole grips or similar. Feel carefully to see if there is any thread there. If it wont come out, you could see if the engine compression will blow it out. Though be careful, and use safety specs etc, in case it suddenly comes out, or any other debris comes flying out (don't lean over the engine looking at it!). If you do get it out, check the thread in the head by screwing in a new glow plug. It should screw in easily and tighten if the thread is undamaged. Don't overtighten though. If the thread is gone, you will have to use a thread insert, (see the tool kit mentioned above). I don't have any videos on this, so you will have to do a google search. Plus search for other extraction methods, as there is probably a lot more detail on the internet on how to get the glow plug out, (more than I can type here). As usual, at your own risk. Let me know how you get on? Hopefully this helps in some way, and you get it fixed soon... 😃
@@doitup Thanks so much very helpful
Thanks. I have a 2003 transit van. 112k. My glow plug warning light flashes occasionally, but not all the time. Engine starts and there’s no white smoke. Any ideas?
Hi, I have a glow plug indicator on the dashboard of a Vauxhall that also appears so briefly you can miss it. Whereas on other vehicles, the indicator stays on a lot longer? As a guess, it's probably down to the circuit design for that particular vehicle (if the vehicle starts and runs fine, with no white smoke). And it may vary from vehicle to vehicle...
Always assume the glow plugs are needed, and wait for them to heat the cylinders, to aid the engine starting process. Glow plugs come on in hot and cold weather, to aid starting and help whilst the engine warms up. However, the length of time they're on may vary (if this is built into the vehicles electronics by design).
If you need to check they're working, check the glow plug resistance and see how long voltage is applied for with a test meter. Or, operate them when removed from the vehicle (example video here... How to Test Glow Plugs Without a Test Meter: th-cam.com/video/YkKsbRHHNS8/w-d-xo.html) and measure how long they glow for. Best to test the glow plugs one at a time, save melting anything nearby!
Hope this helps... 😃
One of my plugs isn't getting a reading , does that mean it's dead ?
Hi, it probably does means it's dead! But, you can do a few checks just to make sure (if you want)...
- If you're measuring resistance, sometimes it's worth checking your meter reads '0' ohms. There's a brief description on how to do check your test meter here: do-it-up.com/vehicles/engine-transmission/diesel-wont-start-when-cold-how-to-fix-glow-plugs/#Check-Your-Test-Meter.
- You could also test the suspect glow plug by removing it from the vehicle and seeing if it works. There's a description on how to do this here: th-cam.com/video/YkKsbRHHNS8/w-d-xo.html.
- Modern glow plugs are not always 12 volts. So if you don't have a 12v supply, it's always worth checking the manufacturer's glow plug data sheets to see what voltage it should be.
Hope this helps, and you get it fixed soon... 😃
@doitup thank you , I'll check it out
How about sir if glow lamp not working what is the possible cause?
Hi, I've not studied the subject, so can only give my best guess... There could be a number of causes, but they can probably be summed up as failure due to old age and wear and tear! A glow plug is stressed throughout it's life. It can go from frozen to glowing red hot in a matter of seconds. Expansion and contraction, oil, rust, corrosive gases, pressure, combustion (explosions), etc, etc. Glow plugs have a hard life! The materials used and quality of manufacture probably have a lot to do with their lifespan, plus... Where you live (starting temperature), number of times the engine is started, how long the engine is run for... They're probably like human beings. Some have a long and happy life while others...
There can also be other factors. My daughter decided to drive through a deep puddle where water was sucked into the engine: do-it-up.com/vehicles/engine-transmission/car-went-through-water-and-died-how-to-fix/. She naturally tried to start the car, but it wouldn't start (hydraulic water lock in the cylinders). When we cleared the cylinders and got the car started. All the glow plugs started to fail. I presume it was because the glow plugs had been trying to boil the water in the cylinders? So, there could be a number of causes, why glow plugs fail. Hope this helps in some way... 😃
I have no power at the leads on the first test.
Hi, If you have a circuit diagram, try and trace the supply with a test meter. If you don't have a circuit diagram, do a search online for your vehicle. To see if there is any information on where components are located. You can also look inside the fuse panel lid, as sometimes relays and fuses are marked up with an indication on what they supply. If you have an idea on where the circuit components are, you can trace the supply back through connectors etc.
When tracing a missing supply, the fastest way home sometimes is to check the mid point in the circuit and then work you way from there... Unfortunately, each vehicle may be different, so it's difficult to give specific help. Also, try and think if there are any interactions with other items on the vehicle. Such as the ignition, temperature etc. They can do fancy things with electronics these days! If there is a break in the circuit, try moving leads (supply on), it can help identify where a break is. Also try making and breaking connectors (with the supply off). There could be a tarnished or dirty connection. Hope this helps and you get it fixed soon... 😃
Great video. Very helpful.
I have one question, how mutch OHM does hè need to be useful.
Thnxxx👍
Hi, I understand that typically, a new glow plug will be 1 to 5 ohms (I've not measured many). For an explanation of glow plug resistance and heat, see do-it-up.com/vehicles/engine-transmission/diesel-wont-start-when-cold-how-to-fix-glow-plugs/#Glow-Plug-Resistance-Explained. Hope this helps... 😃
@@doitupcan you use instead of beeping with a multimeter als use a 12V voltage finder with a light?
It should work the same?
Thanks al lot👍
I've not tried it, but I don't see why not (as it should be the same as testing the continuity with a beeper/buzzer). I have another video that may help. It shows how to test glow plugs without using a test meter: th-cam.com/video/YkKsbRHHNS8/w-d-xo.html, as not everyone has a test meter to hand in their toolbox... 😀
@@doitup thank you so mutch for help
No problem, I hope it all works out and you get it fixed.
Thanx sr g 🙏🙏🙏🙏🙏🙏
No problem, I hope it helped... 😃
Will this work with glow plugs used in small nitro engines like the ones in rc cars
Hi, I've never tested glow plugs in small nitro engines? But i'm guessing the principle would be the same. Give it a go. I hope it works out for you... 😃
@@doitup I used a glow plug igniter from Amazon to test them and they work fine but used the multimeter to check all the other electrical components and determined that everything looks like it should work perfectly but nothing works at all 😂 those nitro engines are a bit of a pain wish me luck lol
P.S. I posted another reply before this one but it disappeared on me so hopefully it doesn’t show two replies now
Hi, I'm glad you managed to get it all checked out. Shame it didn't work afterwards? On the positive side (once you do get it going), you should be pretty good at fixing it should it go wrong again. I had to look up what a glow plug igniter was. Not seen one of those before. My only previous experience with small engines, was with a model aeroplane. You wound the propellor back on a spring and let go, to get it started. You had to get your finger out the way pretty quick! Thanks for your reply. Hope you get it fixed soon... 👍😄
@@doitup I also have an rc airplane but all you do is plug in a battery and flip and switch and it usually works, lol
Does it matter if the measurement is made when engine is warm or cold?
Hi, heat will change resistance values, but it's not something that should make a huge difference in the operation of a glow plug. However, if heat changes the actual component, it could make a difference. I.e. if heat caused the expansion of a component that was fractured, the circuit could open or close (dependant on the direction of expansion). and could cause a failure. Sometimes failures like this aren't easily seen, and are hidden from view?
Let us know if you find anything, as it may help others. Hope this helps, and you get it fixed soon.... 😃
I have only 9, 5 volts on the positive side of the glowplug and 12,5 volt on the battery when engine is not running! What could cause this drop in voltage!?
Hi, it could be caused by a number of issues. Bad contacts, connectors, degraded circuits (the voltage passing through a circuit card, old wiring, etc). The best way to determine the cause, is to trace the circuit back and measure the voltage at different points... It can even be an issue with where you connect the test meter (the return path) to measure the voltage (a bad contact).
Note: The glow plugs negative (-ve) connection is the screw thread of the glow plug where it screws into the engine. Therefore the engine, must also have a good return path to the battery. Hope this helps... 😃
Some cars are fitted with 9,5 V glowplugs.
Mine all tested .5
Hi, glow plug resistance is usually between 1 & 6 ohms, dependant on the manufacturer's specifications. So they could be a bit low? The next best thing to do, is check to see if the glow plugs glow... I have another video here: th-cam.com/video/YkKsbRHHNS8/w-d-xo.html, that shows how to test the actual glow plugs. Methods 2 & 3 are what you need.
- Method 2 can be found here: th-cam.com/video/YkKsbRHHNS8/w-d-xo.html?t=358.
- Method 3: can be found here: th-cam.com/video/YkKsbRHHNS8/w-d-xo.html?t=440.
Please note that method 3 is preferable, and safer. Plus you can check the actual supply to the glow plugs and the glow plug timer at the same time. Hope this helps... 😃
Does it matter if vehicle is on or off?
Hi, it's best to take measurements with the engine off for the following reasons:
When you're measuring the voltage, the glow plug timer will need to be operating. I.e. the glow plug timer starts when you put the ignition on. The timer will turn the supply off after 'x' seconds ('x' depends on the vehicle). You may therefore have to turn the ignition on and off several times to check all of the glow plug voltages and timer. Therefore there is no need to start the engine, plus you may be connecting and disconnecting the glow plug leads.
If you're measuring the resistance in place, you should do this with the engine off, so there's no voltage being applied. Resistance of the actual glow plugs is best measured with them removed. However, measuring the resistance with the glow plugs fitted, also checks part of the circuit (their connection to where they're screwed in. Part of the return path back to the battery).
Hope this helps... 😀
I use a battery charger to test its so easy
Hi, it's a great idea, but... You could damage your battery charger? Most 12v battery chargers have an output of between 2 & 10 Amps. If you have a 2A battery charger, then things might get a bit warm. A quick explanation follows...
As an example, one 12v glow plug with a resistance of 1 ohm would draw about 12A, ( I = V/R ). I.e, 12v/1 Ohm = 12A. This isn't exact, as the resistance will change as the glow plug heats up, but it gives a rough idea. If you have a battery charger with a 10A output, you would probably be OK. So, It's a great idea, 👍 but you should check the output of the battery charger before you try... Just in case.
As usual, at your own risk. Hope this helps... 😃
@@doitup never damaged one doing it yet
I wouldn't disagree, but someone will try it with a cheap battery charger... Unfortunately, got to cover your @r&e these days, dot the 'I's & cross the 'T's... 🙁
You didn't show where the end of the black lead connects from the multimeter? Sorry, I must be really stupid as everyone else seems to know this except silly old me.
Hi, I think you're right, so not stupid at all! Not everyone knows how to use a test meter... I always go and forget something somewhere? The negative lead (black) can go on the negative (-ve) of the battery connection, or anywhere where there is bare metal work on the vehicle (often called earth). The bare metal work must be un-insulated and be connected back to the negative side of the battery through the car bodywork (as long as it's not a fiberglass vehicle where a negative cable has to be run back to the battery). There are often earth points on the vehicle's bodywork for connecting any negative leads (usually black) for connection back to the battery, (the vehicle body acts as a cable to the battery).
Earth and negative can be very confusing terms on vehicles, as you would never connect a negative lead to earth on household electrics as this would cause the circuit breaker to trip, the fuse would blow. Or, in the worst case, it could cause a fire! So vehicle electrical naming conventions (and practices), and general electrical naming conventions (and practices) may be different in some cases. It doesn't make it easy... Hope this long winded reply is useful and helps... 😃
@@doitup very helpful and knowledgeable, thank you for sharing your skills
No problem, it's always good to try and help. Hope it wasn't too long winded... 👍
The engine was leaking when you started it...
Hi. Yep, a little puff of smoke... The copper washer on the injector wasn't sealing properly. Carbon build up will seal it after a while. But, then you won't be able to get the injector out easily! For anyone with the same issue, I would recommend stopping the build up of carbon as soon as possible. Replace the copper washer (as soon as practicable), as they don't cost that much. It will save a lot of headaches later... 😃👍
Can i still used the car long drive with glow plug sensor problem?
Hi, If the vehicle runs OK when the engine is warm, it shouldn't be an issue. Glow plugs only usually cause an issue when starting the engine from cold. However, it may depend on the vehicle and how the manufacturer's configured the vehicle to run, (if there is a fault detected). If there are no warning lights and it runs fine when the engine is warm, you can only assume it will probably be OK. Hope this helps... 😃
@@doitup thank you sir for the reply. Last week i have a check engine. When we scan the ecu it says cylinder 2 and 4 glow plug sensor.
The engine is fine no hard starting. Oh by the way may car is Vw golf wagon 2.0 tdi here manila.
Hi, thanks for the update. The general rule is... If the warning light is amber/orange, then it's just warning you that a fault is present and it should be checked. If the warning light is red, then you shouldn't drive the vehicle. If the amber/orange light refers to any safety equipment like brakes, then get it checked ASAP, in case the fault deteriorates. Hope this helps and you manage to get it fixed soon... 😃
Supper
Hi, thank you. Glad you found it useful... 😃
We must hsve totally different meters in Europe...this meter nothing like the one i have...mine has several numbers under omega symbol,others under letter V,other numbers under A
Hi, the test meter used in the video has something called 'auto range' where the meter automatically decides what range, (voltage, resistance range, etc) it should be measuring. To reduce costs, some test meters don't have an auto range and it has to be set manually. For example, if you are expecting to measure 220/240v ac, you have to set the test meter to V~ (Volts ac) and either 600, 500, 400 or 250 for the range, (test meters can have different ranges). The important thing to remember, is to always start at the higher figure and work downwards. As test meters can get damaged by using the wrong range.
In this example, the 250 range (measuring 220/240v ac) should be the best range, but this isn't always the case. The 400 or 500 range may give a more steady reading. If you're still unsure what to do, see if there is a manual for the test meter. If not, there are some good articles available online by doing a google search. Hope this helps... 😃