A few minor observations: Check for vacuum leak, preferably with smoke test machine. Do complete earth service front to back, car is 30 years old. Looks like you may need engine mounts Check cold start valve Generally these are very reliable, yours is just grumpy about something 😮
Hi Jeff First thing you need to do is put the bonnet in ‘service mode’. There are some clips that open bonnet vertically. You will be able to see everything in the engine bay such much clearer……. Just don’t lift the car to the ceiling on your lift with it open. Will do way more damage than the Alfa ding.
Check these first 1. Check for vacuum leaks. 2. Clean or replace the Idle Control Valve (ICV). 3. Clean the throttle body. 4. Check the fuel filter and fuel injectors. 5. Clean or replace the Mass Air Flow (MAF) sensor. 6. Check alternator and battery connections. 7. Inspect the Overvoltage Protection (OVP) relay. 8. Check the Engine Control Module (ECM). 9. Inspect and replace the air filter if necessary. Failing the above 1. Check the fuel pressure regulator. 2. Inspect the spark plugs and ignition system. 3. Check engine compression. 4. Inspect the throttle position sensor (TPS). 5. Check the coolant temperature sensor. 6. Test the oxygen (O2) sensors.
Those 1990's Mercedes all had an issue with the insulation of the wiring, as they changed the polymer that it was insulated with and it degrades and fails all too soon. Many fires have resulted from this issue.
Most of those old Mercs end up "electrician's nightmares" and $1600 to do up a throttle body, "tell them they're dreaming son". The old "Three Pronged Enema" workshops are scammers. I think from the sound of it starting, stumbling, it has an intake air leak Jeff, a perished hose, a buggered gasket a missing bolt etc, check that aspect, do an inlet tract "smoke test".
especially with the surging.... it's trying to makeup for extra air getting in there, so it gives it more gas....until you overcome that leak and the TB starts opening.
Further to the first post. Had the same symptoms with the W201 190E. Stalled at the traffic lights, had to keep the accelerator and brake pedal depressed at the same time stopped at the lights, otherwise the car would stall. Checked with our mechanic, there are 3 relays behind the battery on the passenger side. Fuel Pump, Aircon and Over Voltage Protection Relay. Replacing the Over Voltage Protection Relay fixed the problem. The relay has fuses on top, which in your case may have blown. On TH-cam there is a channel called Mercedes Classics with Pierre Hedary with a video called "Over Voltage Protection Relays - Signs and Symptoms of Failure", gives symptoms and locations of relays for various Mercedes Cars. Our car overheated as well. While steam cleaning the engine bay, I found an unplugged electrical plug and socket under the air cleaner near the fuel injection unit on the motor. Connecting the socket fixed the overheating problem. Our car stammers sometimes accelerating from standstill, probably water in the fuel tank but that's another issue to fix. Hope this helps.
My E220 was one the nicest vehicles I ever had until it wasn't. some idling issues but the bigger issue was using the vehicle, park at the shop and then it would not start again. The Mercedes Benz dealership replaced the engine bay harness, all fuel pumps, filters and soft lines followed by a new throttle body over the better part of a year including direct consulting with Mercedes techs in Germany. One 600km kilometer trip to my small, out of the way home town and I am stranded again with the same result. The local auto electrician traced and identified the ABS relay as the problem. He replaced it and I had my vehicle back. Unfortunately I lost all confidence in it, my dad wanted it and i gave it to him. He used it for many years without any further issues.
Gotta love complex German engineering...... NOT!.... It's amazing how many different opinions as to the cause you got from professionals........ one of them being the dealer. Love the midweek update Jeff. In saying that, I can hear your frustration
What a beautiful arrangement you have. I am very impressed with your work skills. I like your garage so much that I feel like working with you. I am speaking from Bangladesh🇧🇩 bro. And pray for you to God.
nice T shirt. I used to have one of those cars. It was recently sold on Bring A Trailer here in the US. I'm not responsible for all those stickers on it presently.
“Please tune in for our next episode - how to LS swap a W124, part 1” … chasing electric gremlins, not a fun exercise. Like comment subscribe. Patreon for the win
@@HomeBuiltByJeff after seeing this video, a comment you made on Patreon reminded me of the “eco-friendly” wiring harness MB installed in their cars during the 90s. A lot of the forums mentioned many harnesses were replaced by MB under warranty. But the was 15-20 years ago? I’m hoping for you that the gremlins can be evicted without resorting to a complete re-wiring nightmare. I’m sure this wasn’t the next project you planned after the truck …
WOW! Biodegradable wiring !..... What a paradigm from a brand that presents itself for reliable longevity. I'm all for recycling, especially copper from wiring, but to make wiring biodegradeable seems Soooo counter-productive.
@@davidvincent2838 not only mercedes had biodegradable wiring. For example volvo 740 about 1984-86 had disintegrating isolation too. No one designed it in this way, it's rather problem of newer, poor tested material . Maybe it was cheaper?
As others have said do a vacuum leak with smoke machine, check with wiring diagram that the idle motor is working properly and that the sensors that sense how open the throttle is are working properly. You can also look at specialist rebuild services in the UK as they're more plentiful than here and could be the easy option. Shipping wouldn't be that bad. Engine mounts are shot and possibly reason that wire fractured from excessive vibration. She's a good old girl but at 30yrs old is in need of a fair bit of preventative maintenance to keep it running smoothly. Australia kinda sucks when it comes to parts and specialist services for European vehicles and those that exist will really set you back, like $1600 for the throttle body.
I have a Bosch throttle body on myVW 2L 8V ADT engine and I was struggling with a similar issue. I initially adjusted the spring tension on the throttle body flap and then adjusted the idle circuit. It's idling a bit high at the moment. I am learning more about automotive electronics because I would like to fit a new engine management system into it. I replaced my 1.2L Waterboxxer with the 2L VW Golf engine but kept the original digifant EMS. It's time to put on a new EMS and I've decided on Speeduino. Let the fun and learning begin.
Sounds like and air leak that the idle cant compensate for. But youve done a fantastic diagnostic and repair job so far. Keep going. Its just a car . There will be a simple solution.
When drivers that aren't supposed to be projects start giving you issues it can be so frustrating. Hope you get it sorted. I have also seen old and corroded battery cables cause issues
To make it easier to work on the engine , it should be possible to raise the bonnet up to a vertical position by releasing locking levers on both hinges. Good luck with it Jeff.
To my knowledge the w124 did not have bio degrading wires. Had a 96 300D. The bio wires came with new models and started with c class in 93, and e class w210 in 96
No idea if this could relate to your issues but i had almost exactly the same issues with an Alfa 156 years ago. In the end it was a dirty sensor wire in the MAF.
Frig n heck aye.....cars are difficult from this error....mayb from all errors.....hehe....great to c even u get stumped sometimes.....perseverance is the key aye geff....luv your work n ya vids....gives me hope with my project car..... Cary Nz
Hi Jeff my dad had the same problem on his 230 ce it turned out after lots of messing about it was the alternator discharging so a new alternator is needed
This is like reading the articles in Wheels magazine, Dirty Wheels by George Ambrose. He'd go through all the changes and problem solving only to find the cause of the problem wasn't linked directly to the issue. It was something obscure.
I have a 2009 ML320 with 3l diesel, when it is working it is a great car, but I am always fixing something. They used lots under performing parts throughout the car, some are easy to replace, some are big jobs. I am under whelmed that a marquis with a reputation of quality and robustness let it all slip away.
Thanks for the vid jeff. I yelled alternator at the tv when you showed your 13v and parasitic drain. Good job on the throttle body. Does if have a maf sensor? If so try unplugging it to see if it gets better, vac leaks can sometimes be diagnosed by spraying some carb cleaner round while its running. Increase in revs means a vac leak... Hth 🥂
Not kidding jeff but i guessed that fault straight away on the alternator, if you end up replacing the throttle body it has to be coded have you checked for air leaks.
I read title and already can say this about Mercedes built in 1992-1997; (with certain engines, and with little offset in years) Wiring harness deteriorates, whole engine harness and harness inside throttle body etc. Sometimes even in chassis side the insulation cracks off. I have rebuilt 6 harnesses and from experience if car has been driven long enough the ECU is always broken. Sometimes OVP relay can also do some funny business. Air flow sensor voltages check please. Often I have found the 12v+ pin loses power due to ovp relay or whatever. MAF must be original. Cheap aftermarket will not work. If there is problem with wiring harness you must open every plug. All the way through to the glued together ECU -plug! I have found best repair to be; throw every original engine control related into bin and install maxxecu/ ecu of your liking. M111 most parts are luckily cheap but with M104's its cheaper to change engine control than buy 700€ Air flow sensor and 600-1500€ throttle body (ASR vs non-ASR), while pulling your hair out and diagnosing old unreliable junk. And I personally love mercedes. Still whole engine control is junk. Even KE-Jetronic is lovely compared to this HFM/SFI whatever it name was.. Do not buy used engine harness if it is not made in 1998/ or later. ALL fully original harnesses fail that are built in 1992/1993-1997(in middle of -97 became better) and engine is M111, M104, M120, M119, OM606, etc..
And this issue is with multiple chassis. My ex daily W202 C180 made in 1996. I rebuilt harness, throttle body, etc, before there were any problems. Insulation disappeared in my hands when I opened the harness. Got lucky. Never had any problems. My other daily W210 OM606 made in 1996. Injection pump harness broke, oil lever sensor wiring broke, glow plug wiring broke, ABS pump wiring broke.. That i repaired ABS wiring and threw mechanical injection pump in it. Still work in progress.. My sister has S124 280E, Also failed harness, Ecu, Throttle body, MAF, etc. Multiple thousands in and it runs 'OK', time for Maxxecu next, no more repairs for stock junk engine control. And there have been many more, but lets not talk about those.. I've had something like 40-50 Mercedes.. 40-50 in other makes on top of that.. so could say im familiar..
93-97 Mercedes-Benz, BMW, AUDI cars had biodegradable wiring (German mandate, I believe). The whole engine harness and the alternator harness must be looked at.
Regarding the idle, assuming the idle control mechinism is working, my thoughts keep going to a minor vacuum leak... you could try a spray bottle or pinch/squeezing around the vacuum lines to pinpoint it. Also (unrelated) there's quite a tilt when the engine is correcting the idle, are the engine mounts OK?
Owning a 1992 Mercedes W124 E190 4 Cylinder, in the middle of air cleaner is a hole which leads to the fine idle adjustment of the Bosch Fuel injection, evidently this can play havoc, according to my mechanic. My next task is to overhaul the Fuel Injection. Lots of video's on youtube, how hard can it be?
Sounds like Australia needs a Watch Wes Work... or a South Main Auto Repair LLC... - you know, an excellent country mechanic who can track down just about anything.
This era merc has the self bio degrading wiring harnesses, usuallt the top of engine back is the worst, not sure if they still had the AVR relay accross from the battery, another thing that causes issues in earlier 124 and 126 cars, it is an allot box with a red top and a clear flip up cover to a fuse, well known failure for voltage issues and fails after low battery volta too
You probably know this already . I have heard that these Mercs have wiring that was environmentally friendly and the plastic biodegrades over time and can cause a lot of issues, You can get a complete replacement loom which solves the issue
Is there a MAF sensor in there? If so you might try giving it a squirt with MAF cleaner, don't use brake cleaner as it leaves a residue on the hotwire sensor. It's a cheap fix and if your car has a hotwire MAF I now do it every time I do a service.
I do love how you love giving yourself headaches Jeff😂, mabee just buy an old non computerised Australian car for your daily, I’m sure mrs Jeff would look cool in it.👍
I noticed a rodent had eaten into your battery compartment to bonnet seal they love mercedes organic wiring insulation and vacuum pipe work good luck.Moisture in wiring lume is why old mercs are scraped.
It's well understood that Mercedes introduced a wiring type that was 'eco-friendly' and unfortunately biodegradable - where the crumbling insulation results in numerous electrical gremlins. It's been reported that it affects the majority of Mercedes cars manufactured during the period 1992 to 1997 or thereabouts.
hey Jeffrey . my thoughts for free = low oil pressure at idle , timing chain tensioner collapsing with a streched chain due 2 a lack of oil pressure or bad tensioner? that shake is on stall is very baaad !
I noticed signs of a rodent nibbling the foam around the battery area, maybe it got some wiring too. Also, 1993... isn't that the era of Mercedes' biodegradable wiring looms? Needing engine mounts is reason enough to stick a V8 in it, in my book.
Jeff don't listen to all the keyboard knockers as these Old Mercs are very well built and are like working on an old Holden if you think logically just like the Germans did back then. I own 3 x W126 Gen 2 V8's (2 x 560SEC's & 1 x 560SEL) with my own fully equipped workshop & hoist as iam like you a very handy DIY guy handling complete rebuilds of every aspect. The dealer who has been servicing the car for a long time ask questions as to what mechanical work they did to get an idea if this is a recent issue or not As mentioned by others do a smoke test 1st to see if you have a vaccum leak before doing anything else Yes the OVP relay may be faulty which causes erratic engine idle / clean the ICV (idle control valve with carby cleaner as they get gummed up over time and it causes erratic idle Check the spark plug leads at night in the dark to make sure there is no arcing anywhere Assume your spark plugs are all good Plenty of good tuning advice from Pierre on YT Yes those crumbling engine bay wiring harnesses are junk but you can easily redo them yourself with fresh wiring using the existing plug ends unless you can source an aftermarket harness cheap make sure all earth connections to the chassis are cleaned and good contact
They say Alfas are unreliable and Mercedes are reliable. Well I’ve had both brands and I can definitely say the Mercedes I have is more unreliable than all the Alfas I’ve ever had.
Agree 100%. My Mercedes truck has a parasitic voltage drain. Solution. Battery isolation switch. The 2004 Alfa Spider hasn't missed a beat BUT it gets correctly serviced by an Alfa specialist.
Mercedes was reliable about 50 years ago. Then they went much more to the luxury market and when they realized that most of their customers sell the car after 3 years, they decided that whatever happens to the car after that doesn't matter.
Normally just trying to find out what some idiot mechanic did to it in a rush to get it out the door last!! I have had many mercs brake down on me.. but fuel pump issue on low mileage the most common issue
My dad is on his second ce the first he had from new which was a 230 and had that for 20 years and regretted getting rid so he now has a 91 300ce and his loom is not the bio degradable one thankfully but he did have the alternator issue So I think the next episode will be Jeff replacing the wiring loom
I hat having to "punt" by taking a car to a shop... And then, 99 times out of 100 their diag. is wrong and I have to do it over myself anyway.. Just went through that. Ugg.
A few minor observations:
Check for vacuum leak, preferably with smoke test machine.
Do complete earth service front to back, car is 30 years old.
Looks like you may need engine mounts
Check cold start valve
Generally these are very reliable, yours is just grumpy about something 😮
Hi Jeff
First thing you need to do is put the bonnet in ‘service mode’. There are some clips that open bonnet vertically. You will be able to see everything in the engine bay such much clearer……. Just don’t lift the car to the ceiling on your lift with it open. Will do way more damage than the Alfa ding.
Check these first
1. Check for vacuum leaks.
2. Clean or replace the Idle Control Valve (ICV).
3. Clean the throttle body.
4. Check the fuel filter and fuel injectors.
5. Clean or replace the Mass Air Flow (MAF) sensor.
6. Check alternator and battery connections.
7. Inspect the Overvoltage Protection (OVP) relay.
8. Check the Engine Control Module (ECM).
9. Inspect and replace the air filter if necessary.
Failing the above
1. Check the fuel pressure regulator.
2. Inspect the spark plugs and ignition system.
3. Check engine compression.
4. Inspect the throttle position sensor (TPS).
5. Check the coolant temperature sensor.
6. Test the oxygen (O2) sensors.
Great advice and steps
Yeah - vacuum leaks are the worst as they all sorts of issues. Easy to fix when found
Those 1990's Mercedes all had an issue with the insulation of the wiring, as they changed the polymer that it was insulated with and it degrades and fails all too soon. Many fires have resulted from this issue.
Most of those old Mercs end up "electrician's nightmares" and $1600 to do up a throttle body, "tell them they're dreaming son". The old "Three Pronged Enema" workshops are scammers.
I think from the sound of it starting, stumbling, it has an intake air leak Jeff, a perished hose, a buggered gasket a missing bolt etc, check that aspect, do an inlet tract "smoke test".
Yes indeed, it sounds vacuum related
I agree
I think you are on to it. Check for vacuum leaks.
especially with the surging.... it's trying to makeup for extra air getting in there, so it gives it more gas....until you overcome that leak and the TB starts opening.
Further to the first post. Had the same symptoms with the W201 190E. Stalled at the traffic lights, had to keep the accelerator and brake pedal depressed at the same time stopped at the lights, otherwise the car would stall. Checked with our mechanic, there are 3 relays behind the battery on the passenger side. Fuel Pump, Aircon and Over Voltage Protection Relay. Replacing the Over Voltage Protection Relay fixed the problem. The relay has fuses on top, which in your case may have blown. On TH-cam there is a channel called Mercedes Classics with Pierre Hedary with a video called "Over Voltage Protection Relays - Signs and Symptoms of Failure", gives symptoms and locations of relays for various Mercedes Cars. Our car overheated as well. While steam cleaning the engine bay, I found an unplugged electrical plug and socket under the air cleaner near the fuel injection unit on the motor. Connecting the socket fixed the overheating problem. Our car stammers sometimes accelerating from standstill, probably water in the fuel tank but that's another issue to fix. Hope this helps.
I have just received the OVP relay I ordered so I will see if that fixes the issue.
These are great cars once they're sorted out properly. I owned one w124 and 3 w123. Just loved them all. Great job Jeff
My E220 was one the nicest vehicles I ever had until it wasn't. some idling issues but the bigger issue was using the vehicle, park at the shop and then it would not start again. The Mercedes Benz dealership replaced the engine bay harness, all fuel pumps, filters and soft lines followed by a new throttle body over the better part of a year including direct consulting with Mercedes techs in Germany. One 600km kilometer trip to my small, out of the way home town and I am stranded again with the same result. The local auto electrician traced and identified the ABS relay as the problem. He replaced it and I had my vehicle back. Unfortunately I lost all confidence in it, my dad wanted it and i gave it to him. He used it for many years without any further issues.
Love the trottle stop garage T-shirt. Great channel, Trottle stop garage! And so is yours, thank you for letting us come with you on your journey.
Glad you arent like other youtubers who wouldve just bought a bew throttle body. What a guy. Electrical problems really screw things up.
Gotta love complex German engineering...... NOT!.... It's amazing how many different opinions as to the cause you got from professionals........ one of them being the dealer. Love the midweek update Jeff. In saying that, I can hear your frustration
What a beautiful arrangement you have. I am very impressed with your work skills. I like your garage so much that I feel like working with you. I am speaking from Bangladesh🇧🇩 bro. And pray for you to God.
nice T shirt. I used to have one of those cars. It was recently sold on Bring A Trailer here in the US. I'm not responsible for all those stickers on it presently.
“Please tune in for our next episode - how to LS swap a W124, part 1” … chasing electric gremlins, not a fun exercise.
Like comment subscribe. Patreon for the win
I am getting more and more tempted by the day!
@@HomeBuiltByJeff after seeing this video, a comment you made on Patreon reminded me of the “eco-friendly” wiring harness MB installed in their cars during the 90s. A lot of the forums mentioned many harnesses were replaced by MB under warranty. But the was 15-20 years ago?
I’m hoping for you that the gremlins can be evicted without resorting to a complete re-wiring nightmare.
I’m sure this wasn’t the next project you planned after the truck …
This wiring harness does suffer from the Mercedes biodegradable wiring and I am pretty sure that is the issue.
WOW! Biodegradable wiring !..... What a paradigm from a brand that presents itself for reliable longevity. I'm all for recycling, especially copper from wiring, but to make wiring biodegradeable seems Soooo counter-productive.
@@davidvincent2838 not only mercedes had biodegradable wiring. For example volvo 740 about 1984-86 had disintegrating isolation too. No one designed it in this way, it's rather problem of newer, poor tested material . Maybe it was cheaper?
All hail the algorithm, and the legendary longevity of the (in)famous W124.
As others have said do a vacuum leak with smoke machine, check with wiring diagram that the idle motor is working properly and that the sensors that sense how open the throttle is are working properly. You can also look at specialist rebuild services in the UK as they're more plentiful than here and could be the easy option. Shipping wouldn't be that bad.
Engine mounts are shot and possibly reason that wire fractured from excessive vibration. She's a good old girl but at 30yrs old is in need of a fair bit of preventative maintenance to keep it running smoothly.
Australia kinda sucks when it comes to parts and specialist services for European vehicles and those that exist will really set you back, like $1600 for the throttle body.
I absolutely love my w124. They go for ever if you treat them right.
Has same issue with my Audi A4 and battery drain -replaced regulator on alternator and all good
I have a Bosch throttle body on myVW 2L 8V ADT engine and I was struggling with a similar issue. I initially adjusted the spring tension on the throttle body flap and then adjusted the idle circuit. It's idling a bit high at the moment. I am learning more about automotive electronics because I would like to fit a new engine management system into it. I replaced my 1.2L Waterboxxer with the 2L VW Golf engine but kept the original digifant EMS. It's time to put on a new EMS and I've decided on Speeduino. Let the fun and learning begin.
I'm sure you can find the problem and solve it, I saw how you built the Alfa.🙂
Bob is old, but I don't think he's worn out.
Worth a try🍀
Midweek Jeff! Nice!
Sounds like and air leak that the idle cant compensate for. But youve done a fantastic diagnostic and repair job so far. Keep going. Its just a car . There will be a simple solution.
When drivers that aren't supposed to be projects start giving you issues it can be so frustrating. Hope you get it sorted. I have also seen old and corroded battery cables cause issues
Only 60 days a year bc it’s broken the other 305? Jesting aside, I enjoy how you unpack a problem.
I'm just here for the fun facts with Mrs. Jeff
To make it easier to work on the engine , it should be possible to raise the bonnet up to a vertical position by releasing locking levers on both hinges.
Good luck with it Jeff.
To my knowledge the w124 did not have bio degrading wires. Had a 96 300D. The bio wires came with new models and started with c class in 93, and e class w210 in 96
100% has the biodegradeable wires. Every wire in the engine bay is falling apart.
@@HomeBuiltByJeff - The wires are horrible to work with. Good luck
No idea if this could relate to your issues but i had almost exactly the same issues with an Alfa 156 years ago. In the end it was a dirty sensor wire in the MAF.
Frig n heck aye.....cars are difficult from this error....mayb from all errors.....hehe....great to c even u get stumped sometimes.....perseverance is the key aye geff....luv your work n ya vids....gives me hope with my project car.....
Cary
Nz
Hi Jeff my dad had the same problem on his 230 ce it turned out after lots of messing about it was the alternator discharging so a new alternator is needed
As I did in this episode and it fixed that side.
I'd have to agree with the people saying maf / map sensor for the bad idle.
Most cars have a failsafe mode if you unplug it to confirm.
the old W124 is one of the best mercs ever made
Excellent
Mid week with Jeff
This is like reading the articles in Wheels magazine, Dirty Wheels by George Ambrose. He'd go through all the changes and problem solving only to find the cause of the problem wasn't linked directly to the issue. It was something obscure.
I had a W202 with this engine and a manual box. I think the six-cylinder suits these cars better, especially the W124 beeing a bigger and heavier car
It is extremely slow with this little 4 cylinder
Looking at that wobble when it is about to stall, are your engine mounts shot???
Have you checked the Positive Crankcase Vetilation system? The BMW has AN INCREDIBLY complex system and if any thing goes wrong it won't idle.
I have a 2009 ML320 with 3l diesel, when it is working it is a great car, but I am always fixing something. They used lots under performing parts throughout the car, some are easy to replace, some are big jobs. I am under whelmed that a marquis with a reputation of quality and robustness let it all slip away.
Thanks for the vid jeff. I yelled alternator at the tv when you showed your 13v and parasitic drain. Good job on the throttle body. Does if have a maf sensor? If so try unplugging it to see if it gets better, vac leaks can sometimes be diagnosed by spraying some carb cleaner round while its running. Increase in revs means a vac leak... Hth 🥂
I knew exactly what was wrong. My Lexus RX330 just did the same thing, except it killed my battery.😀
Not kidding jeff but i guessed that fault straight away on the alternator, if you end up replacing the throttle body it has to be coded have you checked for air leaks.
I read title and already can say this about Mercedes built in 1992-1997; (with certain engines, and with little offset in years)
Wiring harness deteriorates, whole engine harness and harness inside throttle body etc. Sometimes even in chassis side the insulation cracks off. I have rebuilt 6 harnesses and from experience if car has been driven long enough the ECU is always broken. Sometimes OVP relay can also do some funny business.
Air flow sensor voltages check please. Often I have found the 12v+ pin loses power due to ovp relay or whatever. MAF must be original. Cheap aftermarket will not work.
If there is problem with wiring harness you must open every plug. All the way through to the glued together ECU -plug!
I have found best repair to be; throw every original engine control related into bin and install maxxecu/ ecu of your liking. M111 most parts are luckily cheap but with M104's its cheaper to change engine control than buy 700€ Air flow sensor and 600-1500€ throttle body (ASR vs non-ASR), while pulling your hair out and diagnosing old unreliable junk. And I personally love mercedes. Still whole engine control is junk. Even KE-Jetronic is lovely compared to this HFM/SFI whatever it name was..
Do not buy used engine harness if it is not made in 1998/ or later. ALL fully original harnesses fail that are built in 1992/1993-1997(in middle of -97 became better) and engine is M111, M104, M120, M119, OM606, etc..
And this issue is with multiple chassis.
My ex daily W202 C180 made in 1996. I rebuilt harness, throttle body, etc, before there were any problems. Insulation disappeared in my hands when I opened the harness. Got lucky. Never had any problems.
My other daily W210 OM606 made in 1996. Injection pump harness broke, oil lever sensor wiring broke, glow plug wiring broke, ABS pump wiring broke.. That i repaired ABS wiring and threw mechanical injection pump in it. Still work in progress..
My sister has S124 280E, Also failed harness, Ecu, Throttle body, MAF, etc. Multiple thousands in and it runs 'OK', time for Maxxecu next, no more repairs for stock junk engine control.
And there have been many more, but lets not talk about those.. I've had something like 40-50 Mercedes.. 40-50 in other makes on top of that.. so could say im familiar..
I don't know if I'm right, but I think I saw an idle screw on the throttle body, could that be an issue?
As always, nice to see you working 🙂👍👍
93-97 Mercedes-Benz, BMW, AUDI cars had biodegradable wiring (German mandate, I believe). The whole engine harness and the alternator harness must be looked at.
"The" before consonants. "Thee" before vowels. In Aus it is "thee" before everything. Thanks for posting thee video.
Pronunciation variations occur in many languages and countries 🤷♀
@@seanalexander9531Joking of course. I live in South Africa. Here a traffic light is called a "robot"
Regarding the idle, assuming the idle control mechinism is working, my thoughts keep going to a minor vacuum leak... you could try a spray bottle or pinch/squeezing around the vacuum lines to pinpoint it. Also (unrelated) there's quite a tilt when the engine is correcting the idle, are the engine mounts OK?
Its like 30 years old chill my dude!!!☺️
Owning a 1992 Mercedes W124 E190 4 Cylinder, in the middle of air cleaner is a hole which leads to the fine idle adjustment of the Bosch Fuel injection, evidently this can play havoc, according to my mechanic. My next task is to overhaul the Fuel Injection. Lots of video's on youtube, how hard can it be?
Poor Barb just needs a bit of love, goof luck
Sounds like Australia needs a Watch Wes Work... or a South Main Auto Repair LLC... - you know, an excellent country mechanic who can track down just about anything.
Sounds like a vacuum leak. Check for any broken vacuum lines. Leaky injector seals or any leak on the inlet manifold.
Sounds like exactly the same issue we had on a 1995 E230. I think we paid $6000 for a rebuilt one from Mercedes dealer.
This era merc has the self bio degrading wiring harnesses, usuallt the top of engine back is the worst, not sure if they still had the AVR relay accross from the battery, another thing that causes issues in earlier 124 and 126 cars, it is an allot box with a red top and a clear flip up cover to a fuse, well known failure for voltage issues and fails after low battery volta too
After owning three Mercedes Benzes, when they start giving trouble, get rid of it. But when they run well, there is no end.
You probably know this already . I have heard that these Mercs have wiring that was environmentally friendly and the plastic biodegrades over time and can cause a lot of issues, You can get a complete replacement loom which solves the issue
Is there a MAF sensor in there? If so you might try giving it a squirt with MAF cleaner, don't use brake cleaner as it leaves a residue on the hotwire sensor. It's a cheap fix and if your car has a hotwire MAF I now do it every time I do a service.
and never clean it with the engine running! if not you burn it.
I tried that too but unfortunately didn't fix the idle.
I do love how you love giving yourself headaches Jeff😂, mabee just buy an old non computerised Australian car for your daily, I’m sure mrs Jeff would look cool in it.👍
how I would love to se this with a domestic to australia inline 6 swap 😂 will a Barra fit ?
I noticed a rodent had eaten into your battery compartment to bonnet seal they love mercedes organic wiring insulation and vacuum pipe work good luck.Moisture in wiring lume is why old mercs are scraped.
Completely unrelated to the problem at hand: are the engine mounts still okay? Looks a bit shaky.
Vacuum leak ?
Thumbs up for the Volvo t-shirt
It's well understood that Mercedes introduced a wiring type that was 'eco-friendly' and unfortunately biodegradable - where the crumbling insulation results in numerous electrical gremlins. It's been reported that it affects the majority of Mercedes cars manufactured during the period 1992 to 1997 or thereabouts.
to be fair you would have to be a mechanic or auto elec to immediately go alternator diodes!!! trade trained does have some benefits :)
Fuel problem, or Airleak? Also Check the Sparkplugs/kable and Coils
hey Jeffrey . my thoughts for free = low oil pressure at idle , timing chain tensioner collapsing with a streched chain due 2 a lack of oil pressure or bad tensioner? that shake is on stall is very baaad !
I noticed signs of a rodent nibbling the foam around the battery area, maybe it got some wiring too.
Also, 1993... isn't that the era of Mercedes' biodegradable wiring looms?
Needing engine mounts is reason enough to stick a V8 in it, in my book.
Jeff whats with the 2 min 20 sec of blank screen at the end.
Sorry - just wanted yo to know
Haha. I didn't even see that in the edit. I messed up again ;)
@@HomeBuiltByJeff ahhhh life.
At least the projects move forward
Jeff don't listen to all the keyboard knockers as these Old Mercs are very well built and are like working on an old Holden if you think logically just like the Germans did back then.
I own 3 x W126 Gen 2 V8's (2 x 560SEC's & 1 x 560SEL) with my own fully equipped workshop & hoist as iam like you a very handy DIY guy handling complete rebuilds of every aspect.
The dealer who has been servicing the car for a long time ask questions as to what mechanical work they did to get an idea if this is a recent issue or not
As mentioned by others do a smoke test 1st to see if you have a vaccum leak before doing anything else
Yes the OVP relay may be faulty which causes erratic engine idle / clean the ICV (idle control valve with carby cleaner as they get gummed up over time and it causes erratic idle
Check the spark plug leads at night in the dark to make sure there is no arcing anywhere
Assume your spark plugs are all good
Plenty of good tuning advice from Pierre on YT
Yes those crumbling engine bay wiring harnesses are junk but you can easily redo them yourself with fresh wiring using the existing plug ends unless you can source an aftermarket harness cheap
make sure all earth connections to the chassis are cleaned and good contact
Next vid out soon. OVP replaced, and this car doesn't have an ICV. Still head scratching.
vacuum lines leaking?
tired fuel pump ?
They say Alfas are unreliable and Mercedes are reliable. Well I’ve had both brands and I can definitely say the Mercedes I have is more unreliable than all the Alfas I’ve ever had.
Agree 100%. My Mercedes truck has a parasitic voltage drain. Solution. Battery isolation switch. The 2004 Alfa Spider hasn't missed a beat BUT it gets correctly serviced by an Alfa specialist.
Mercedes was reliable about 50 years ago. Then they went much more to the luxury market and when they realized that most of their customers sell the car after 3 years, they decided that whatever happens to the car after that doesn't matter.
Jeff you are close enough to work on the Foyota😁
You have to remember that the Mercedes is just a holden in Germany. 😜
I image Mrs Jeff’s day job is a weather forecaster cause she’s so pretty 😊
All hail the algorithm 🤘
Jeff be careful mercs from 93 to 96 had biodegradable wiring harnesses
You nailed it.
Put it on a Link ECU, it will be cheaper and easier.
Totally forgot you bought his thing. Another project ....😅
Check your fuel system mate
MERCEDES USUALLY NEED 14.6 VOLTS TO MAKE EVERYTHING HAPPY,
Barb wants a Barra swap
Air leak somewhere??
What happened to the 911?
Would have been better off with a 190e Cosworth replica!
vac leak or a sensor doesn´t work correct
Sounds kinda like an air leak?
hello Soulution For Fixing This Car is Tow it to Jonkyard If you Find another one like this Disel Engine Is Best DIY Fix.
check your wiring harness this is the age of the biodegradeble harness, wires could be catching each other!!
👍
Normally just trying to find out what some idiot mechanic did to it in a rush to get it out the door last!! I have had many mercs brake down on me.. but fuel pump issue on low mileage the most common issue
Is it from the time when they used biodegradable wiring looms? If so, it may be a break or short somewhere.
My dad is on his second ce the first he had from new which was a 230 and had that for 20 years and regretted getting rid so he now has a 91 300ce and his loom is not the bio degradable one thankfully but he did have the alternator issue
So I think the next episode will be Jeff replacing the wiring loom
Mercedes are great, until they aren't... The license on all of my vehicles here in Tennessee are the same, $29 a year... New or old.
Your wife is extremely tolerant if she's letting you call this a shared daily driver!!
I hat having to "punt" by taking a car to a shop... And then, 99 times out of 100 their diag. is wrong and I have to do it over myself anyway.. Just went through that. Ugg.
$1600 Is Piss Take. You could get a Haltec and Throttle Bodies for that kind of Money 😮
Except they won't work on this car without changing everything.
where's part 1?
Added to the playlist
Mass airfow sensor or vacuum leak??
Cheers 👍💪✌
If you solder repaired the wire there may now be more resistance causing an issue. Is the idle adjustment screw & seat clean? Just a thought.