saintz

I left the car idling for a long time, and when I came back, the check engine light was on. It seems it got very hot. I turned the car off, pulled the battery, and plugged it back in. Car ran fine when restarted. But, when I floor it, it throws a CEL again and starts to run like a total dog. Gears all still work, so it's not in limp mode, but feels like it. Restart the car, and it's fine again, until I floor it.

Pulled codes and have misfire on cylinders 4, 5, and 6.

I'm assuming the passenger coil pack went out. Any other ideas? Clogged cat sounds unlikely.

maxwerks

Sounds like either coil pack or sparks , problem is it is a shame not to change the coil pack if you change the sparks .. but check the Fuel pressure first and make sure you have the right pressure ... Clogged cat is very easy to diagnose compared to the other possibilities :

It is not exactly what happened to me but similar .. if I am driving for lets say 45 minutes , park the car , then start it again few minutes later ... same thing as you describe .....park it over night or for the afternoon , let it cool , the CEL wont come on car is fine ... then it will happen more frequent .. even if the car had a chance to cool off .. it would shake , run like a dog ... then I would shut it off ... restart again .. sometimes it will just go back to perfect running sometimes not !!!! Mercedes first said , random misfire .. on the few times I took it to them , they cleared the error , cleared the memory , car ran fine .. then same thing started happening again ... we changed the Fuel pump , fuel controller .... that took car of things for a week .. then inevitably .. both Coil packs , all sparks , ICM was changed !!

Becks Imports

99.999% chance it's the coil pack.

Can be had new for $825 or so if you look hard.

Bruce

maxwerks

Saintz as Becks said most likely it is the coil pack but , what I went through is what I will tell you , it all depends how long you want to keep the car , best thing to do is to change the spark plugs when you change the coil pack .. but that means it is not the best thing to do one bank only ... one thing leads to another then you end up changing both banks ... best is check the fuel pressure first , there were 3 or 4 different part numbers for the Fuel pump , the later on is the better from what I was told ..and if you change the fuel pump YOU MUST change the controller along with it ... it is one of those things which have to be done anyway , if you dont want to go ahead and just change the coil pack I would start from the Fuel pressure / pump point and go from there . I dont now what miles you have on yours but I bough mine with 43K miles and that started to happen at 44K miles !! Keep us posted and best of luck

maxwerks

The one things I can never forget once I bought my TT CL600 .. I would park the car after coming back from work .. and ours later go outside and still feel the incredible heat over the hood ... I have never ever noticed a car or an engine which retains heat that much and that long !!! when I found out that the ICM is bolted right above the intake manifold I was shocked thinking how much heat that thing is usually subjected to on a regular basis ... hat cant be healthy for an engine electronic module ..then again there are may V12s with 100K + miles out there so it must take it for a while ..yes I know about the upgraded IC pump and Radiator , and an auxillary coolant tank remedies .. but the CL600 should nt have to rely on that on normal basis ... so without that , I always wondered about how limited are the ways for that car to expel heat ! it just seems to stay there forever !

saintz

The cooling on these things is terrible. Given their popularity in the middle east, I don't know why they don't have a better system.

saintz

Bruce, where? Thanks!

radride

Agreed. They should of had vented hoods from the factory to help get the heat out of the engine bay.

R.K.

Becks Imports

It's $200 for the info.

This is the place last time I checked:

A1 Mercedes
4750 NE 11th Ave
Ft. Lauderdale, FL 33334
1-855-287-2217

Bruce

saintz

Ok, I'm going to swap the coil pack and while I'm in there, replace all the spark plugs.

Ignition coil, parts.com under Electrical>Ignition, available in right (passenger, cylinders 1-6) and left (driver, cylinders 7-12)

Insulator boot, part number A0001590080, found on parts.com by searching 0001590080 (in case I break some on the coil pack I am not replacing, new coil pack comes with them)

24 x Bosch OEM plugs on autohausaz.com

saintz

Bruce, the place you had recommended wouldn't sell them at that price unless you sent your current module in for diagnosis and repair and they were unable to repair. Still, a great deal if you want to repair it. I figured I'd rather slap a new one in and not have to have the downtime while they repaired and tested it. Thanks though.

biker349

i believe i've heard some bad things about A1 mercedes. am i wrong? am i talking about another ft. lauderdale co.?

saintz

I think it's 4-Mercedes with the bad wrap for repairing them.
https://mbworld.org/forums/cl55-amg-...coil-pack.html

I talked to the tech at A1, and he sounded very knowledgeable. He said it takes a week or two, but they can fix them for potentially a lot less, and then they bench test it and then install it in their car to test. You have to send the coil pack and the ICM so they test both.

radride

^^Keep us posted. This sounds interesting.

R.K.

maxwerks

Whats the latest Saintz . hope all is well

saintz

New coil is sitting in the garage. Waiting on plugs from autohausaz. Might as well do them while I'm there.

maxwerks

do the plugs for sure .. remember , ask them to send the recent production plugs , apparently , the pre gapped ones from earlier production were pregapped wrong .. MB issued an update for the specs later ( I think but dont quote me 0.8mm ) AutohausAZ should know about that . best of luck

Merzman

Does anyone know of an approved sequence for cheking the misfire issue? Mine does the same. Disconnect battery to clear codes results in smooth running most times for about 100 miles, then it all starts again. All started with cold weather and the oil leak into the harness. Fixed oil, changed out harness. Has not run right since even with new coil pack and O2 sensors. Seems it might be a throttle position sensor or MAF sensor. Fuel could be an issue. Problem with this car is ICU over thinks and shuts things down to keep emissions in spec.

saintz

I would check the Ignition Control Module.

drewk88

Insulator Boots $2.39 each.

https://importecautoparts.com/parts/...59%2000%2080/3