CEL and coils?
Thread Starter
Super Member
Joined: Sep 2011
Posts: 687
Likes: 10
From: SoCal
2014 E63s
CEL and coils?
So my CEL came on last week with codes
P209900 Mixture too rich downstream of the catalytic converter(cylinder bank 2) there is a general failure - stored.
P030085 Combustion misfiring has been detected. There is a signal fault or the message is faulty - stored.
Looks like cylinders 6 & 7. I'm being told its most likely the coils. Rather than changing parts to find out if in fact it is the coils I figured i'd throw it out here first, maybe someone knows better. My car is RENNtech tuned with BMC filters and updated spark plugs.
Can anyone help with this?
P209900 Mixture too rich downstream of the catalytic converter(cylinder bank 2) there is a general failure - stored.
P030085 Combustion misfiring has been detected. There is a signal fault or the message is faulty - stored.
Looks like cylinders 6 & 7. I'm being told its most likely the coils. Rather than changing parts to find out if in fact it is the coils I figured i'd throw it out here first, maybe someone knows better. My car is RENNtech tuned with BMC filters and updated spark plugs.
Can anyone help with this?
Member
Joined: Jun 2015
Posts: 113
Likes: 12
From: YUL
2012 E63 AMG Wagon
Don't know if this will be of much help, but my 2012 is coming up on 70k miles and I've been noticing that acceleration isn't as smooth as it should be. Don't have a code reader so unsure if I have a P030085 code happening like you, but I've also recently changed my plugs after getting a full RennTech tune about 6 months ago. The "missing" on acceleration was happening prior to the tune and I figured new plugs would cure it, but it's still there just not quite as bad.
Some say the coils can last the life of the car, or at least to 100k miles. But I had a 2002 911 that also had a couple of coils go bad right around this mileage, and so last week I ordered a batch of new ones and will change them out and hope for the best.
Some say the coils can last the life of the car, or at least to 100k miles. But I had a 2002 911 that also had a couple of coils go bad right around this mileage, and so last week I ordered a batch of new ones and will change them out and hope for the best.
Thread Starter
Super Member
Joined: Sep 2011
Posts: 687
Likes: 10
From: SoCal
2014 E63s
Replaced coils 6&7, reset the codes and its running perfect. Tech says theres a good chance the misfire will come back due to other coils going out. If that happens i'll change the other 6 and call it a day.
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Thread Starter
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From: Bay Area, California
2015 E63s AMG, 2020 GLC 43 AMG
Slightly different issue regarding coils here, but I thought you guys might want to hear about it. Some of you have already heard in other threads by me.
Granted this is in regards to M156 coils. I had #5 coil on the 2011 actually short to ground driving to work one day. When this occurred, the main fuse for the entire ignition blew. When this happened, while the engine was still on and turning freeway rpm's, RAW FUEL WAS SENT STRAIGHT TO THE CATS! This caused flames to shoot out of the exhaust and blew up the cats. Someone on the freeway actually called the fire dept and while I was speaking to roadside for a tow, a fire engine pulled in behind me and blocked off 1 lane of the freeway. LOL. Fireman said "someone called in flames shooting from the rear of a Mercedes". Damn, I wish I had video of that! Start a thread titled "Check out my new tune".
Anyway, I thought I would share this to point out a coil failing and causing a performance issue temporarily is not that bad compared to having one short to ground. Also, The AMG tech at the dealer said that normally when a coil fails the ECU will stop delivering fuel to that cylinder to keep from damaging the exhaust. But apparently the madmen in Stuttgart didn't consider all coils failing as a result of an ignition fuse. Oops. He also said he has only seen what happened to my 2011 one other time in a Maybach! Good company I guess. lol
Granted this is in regards to M156 coils. I had #5 coil on the 2011 actually short to ground driving to work one day. When this occurred, the main fuse for the entire ignition blew. When this happened, while the engine was still on and turning freeway rpm's, RAW FUEL WAS SENT STRAIGHT TO THE CATS! This caused flames to shoot out of the exhaust and blew up the cats. Someone on the freeway actually called the fire dept and while I was speaking to roadside for a tow, a fire engine pulled in behind me and blocked off 1 lane of the freeway. LOL. Fireman said "someone called in flames shooting from the rear of a Mercedes". Damn, I wish I had video of that! Start a thread titled "Check out my new tune".
Anyway, I thought I would share this to point out a coil failing and causing a performance issue temporarily is not that bad compared to having one short to ground. Also, The AMG tech at the dealer said that normally when a coil fails the ECU will stop delivering fuel to that cylinder to keep from damaging the exhaust. But apparently the madmen in Stuttgart didn't consider all coils failing as a result of an ignition fuse. Oops. He also said he has only seen what happened to my 2011 one other time in a Maybach! Good company I guess. lol
