2012 C300 sport 4matic here. This was a super helpful video. With the proper tools, and following instructions as shown, took me 1.5hrs. The plugs in the back and on the right side of the engine require some tricky angles, so come ready with multiple size extensions. With some patience and a cold beer, this was a simple and rewarding job. Excellent video, I could feel a difference just starting the car!
Excellent video. I have a 2008 C300 that I purchased new. 11 year old "garage queen" in showroom condition with only 24K miles. It runs great but I want to change plugs due to the age. I noticed the coils in the past, when I replaced the air filters but I did not expect it to be so easy. No surprises. Thanks for the video.
Glad you shed some light on the subject. I'm thinking about scooping one of these up and I wanted to get a look at the engine. Much easier than any of the FWD cars I've had in recent years. 1992 Taurus SHO, 1997 Taurus SHO, 2000 Maxima.. The newer the car, the harder the work was just another reason I want all rear wheel drive cars. One thing, those plugs looked like they could have used a few hours or an overnight pre-soak of WD-40 or a penetration aerosol. My '06 Mustang GT is THE WORST! All the 3V Ford engines are notorious for having the 100,000 mile spark plugs break the tip into the head.
Very helpful video. I want you to know I really appreciate you posting it. I'm about to replace my ignition coils and spark plugs, and this is just a solid help. Thank you.
The filter cover has a clamp that is holding it, that is the reason it took you a little bit more effort to remove, make sure to loosen the clamp first. Thanks for the video
You are correct that the clamp should normally be at the back of the air filter housing (the area closest to the firewall). Unfortunately in the case of my car it was missing (probably the shop that did prior maintenance on the car broke it off).
hot take: the aftermarket japanese plugs are better and cheaper than the bosch plugs, also mercedes is moving away from the iridums back to copper because the iridium spark isn't hot enough and it's causing misfires. they still fit cars from the factory with the iridium plugs, but they have TSBs out now suggesting you switch to copper. check TSB LI15.10-P-051968 and switch to coppers. also yeah the OE plugs specifically tell you not to gap them so
Thank you for sharing this. A quick search indicated that this applies to certain 2011 - 2012 model year vehicles ( www.tsbsearch.com/Mercedes-Benz/LI15.10-P-051968 ). Do you have access to the TSB that show all of the vehicles that this applies to an the recommended spark plug part #s?
Like someone asked already, I would recommend anti-seize compound on threads. Careful with the anti-seize, do not get it on the ceramic insulator or the electrode.
I would not recommend using antisieze on these plugs. You have to be careful... If the plugs have a coating on the threads they may not need it. If you use it and they don't need it, you will apply too much preload on the threads at a given level of applied torque, essentially the same as if you had overtorqued them without the antisieze. Contact the maker of the plugs if you are not sure. I'm a mechanical engineer and I deal with threads / bolts every day.
You are correct. I caught that after I stopped recording and have subsequently attached the hose. I believe someone else pointed that out before and captured it in the comments below.
I replaced the spark plugs on this car a while ago, and if I remember correctly, it did not have the check engine light on. It was just due for a scheduled maintenance replacement. If you do have a check engine light on, it could be a spark, plug problem, but often it is related to a bad coil. You can check the coils by moving them from one to another cylinder and reading on the code reader, if the misfire trouble code moves from one to another cylinder. I hope this helps.
The spark plugs should not get any power with the ignition off, but it is also good practice to disconnect the negative terminal of your car battery when working on anything electrical.
2012 C300 sport 4matic here. This was a super helpful video. With the proper tools, and following instructions as shown, took me 1.5hrs. The plugs in the back and on the right side of the engine require some tricky angles, so come ready with multiple size extensions. With some patience and a cold beer, this was a simple and rewarding job. Excellent video, I could feel a difference just starting the car!
Same
I’ve never come across a video that used that particular craftsman torque wrench, I’ve been using that same one since 2005.
Thank you for the video!! Followed step by step and got it done in no time.
Excellent video. I have a 2008 C300 that I purchased new. 11 year old "garage queen" in showroom condition with only 24K miles. It runs great but I want to change plugs due to the age. I noticed the coils in the past, when I replaced the air filters but I did not expect it to be so easy. No surprises. Thanks for the video.
Thank you for the video. I've been able to change the spark plugs by myself thanks to you.
Glad you shed some light on the subject. I'm thinking about scooping one of these up and I wanted to get a look at the engine. Much easier than any of the FWD cars I've had in recent years. 1992 Taurus SHO, 1997 Taurus SHO, 2000 Maxima.. The newer the car, the harder the work was just another reason I want all rear wheel drive cars.
One thing, those plugs looked like they could have used a few hours or an overnight pre-soak of WD-40 or a penetration aerosol. My '06 Mustang GT is THE WORST! All the 3V Ford engines are notorious for having the 100,000 mile spark plugs break the tip into the head.
dude thank you for that I did not want to go to the dealership thank you very much
Thank you for the information of the right type of spark plugs.... it really helps me alot.. 🙏👍👍
Very helpful video. I want you to know I really appreciate you posting it. I'm about to replace my ignition coils and spark plugs, and this is just a solid help. Thank you.
You are welcome. I am glad to hear the video was helpful.
thank you that coil clip demonstration helped out a lot.
Excellent video. Shows me exactly what I need to do. Thanks!
You forgot to connect the third tube in the air filter casing!!! Good luck with that check engine light.
That's true, he totally forgot
That's called the secondary air injection pump transfer hose.
And he also forgot anti sieze on his spark plug threads before he screwed them in
Just changed mine out in like 20 minutes ! Thanks !
I know your video is old so forgive me, but can you tell me what size socket you had to use to pull out the spark plug?
Thank you for a very detailed video. Nicely done.
What size socket to use to loss the spark plug
Saved myself $300... Did this on my GLK350 which has the same engine.
The filter cover has a clamp that is holding it, that is the reason it took you a little bit more effort to remove, make sure to loosen the clamp first. Thanks for the video
You are correct that the clamp should normally be at the back of the air filter housing (the area closest to the firewall). Unfortunately in the case of my car it was missing (probably the shop that did prior maintenance on the car broke it off).
Thank u so much for this informative video, God bless
You are welcome.
hot take: the aftermarket japanese plugs are better and cheaper than the bosch plugs, also mercedes is moving away from the iridums back to copper because the iridium spark isn't hot enough and it's causing misfires. they still fit cars from the factory with the iridium plugs, but they have TSBs out now suggesting you switch to copper. check TSB LI15.10-P-051968 and switch to coppers.
also yeah the OE plugs specifically tell you not to gap them so
Thank you for sharing this. A quick search indicated that this applies to certain 2011 - 2012 model year vehicles ( www.tsbsearch.com/Mercedes-Benz/LI15.10-P-051968 ). Do you have access to the TSB that show all of the vehicles that this applies to an the recommended spark plug part #s?
Like someone asked already, I would recommend anti-seize compound on threads. Careful with the anti-seize, do not get it on the ceramic insulator or the electrode.
I would not recommend using antisieze on these plugs. You have to be careful... If the plugs have a coating on the threads they may not need it. If you use it and they don't need it, you will apply too much preload on the threads at a given level of applied torque, essentially the same as if you had overtorqued them without the antisieze. Contact the maker of the plugs if you are not sure. I'm a mechanical engineer and I deal with threads / bolts every day.
Good demo video.
what about anti seize for the plugs, is it needed
Thanks for that!!
Thank you very much
How do I know which spark plug needs changed ⁉️ while the car is in parked running it shakes
Now
I may be mistaken but, didn't you miss that middle hose that goes on the air filter housing assembly?
You are correct. I caught that after I stopped recording and have subsequently attached the hose. I believe someone else pointed that out before and captured it in the comments below.
Did the engine red light due to misfiring disappear
I replaced the spark plugs on this car a while ago, and if I remember correctly, it did not have the check engine light on. It was just due for a scheduled maintenance replacement. If you do have a check engine light on, it could be a spark, plug problem, but often it is related to a bad coil. You can check the coils by moving them from one to another cylinder and reading on the code reader, if the misfire trouble code moves from one to another cylinder. I hope this helps.
Thx for not saying the socket size smh
Yes That early a lesson 04.
just like any other car
how much would Benz dealer take for this? 500? 1000? $
400
$750 now(2018)
Eyal Mares for changing all spark plugs??
Eyal Mares its 430 here at MA
Buying six spark plugs on Amazon set me back $45 or so. Definitely worth it to do it yourself.
do you need a deep socket if you have extension bar?
I used a deep spark plug socket with a rubber line inside to hold the spark plug.
would this process change much on a 2009? c300
I believe model year 2008 and 2009 C300 have the same M272 engine.
This is not for 2013 C300
What is the socket size
If I recall correctly, the spark plug socket size is 5/8.
Do you have to disconnect the battery terminal
The spark plugs should not get any power with the ignition off, but it is also good practice to disconnect the negative terminal of your car battery when working on anything electrical.