Hey guys, I have to say that being able to have internet and this knowledge from all of you via this website is amazing with that being said I have recently purchased a 2002 CL600 3 days ago and it has multiple problems, the RPM at a stop light stay at around 600, the car has no power for a V12 it idles/feels unresponsive. I've had the car running and driven for about 1 hr turn it off then come back to it 30 minutes later start it starts fine but immediately stalls bc the RPM seem to be going down oh and CEL is on...

Here is the list of codes from autozone:

P1422 [BLANK]
P0422 Main Catalyst Efficiency Below Threshold (Bank 1)
P0100 Mass or Volume Air Flow Circuit
P0311 Cylinder 11 Misfire Detected
P0312 Cylinder 12 Misfire Detected
P0308 Cylinder 8 Misfire Detected
P0300 Mulitple/Random Misfire Detected
P0221 Throttle/Pedal Position Switch B Circuit Range/Performance
P0307 Cylinder 7 Misfire Detected
P0309 Cylinder 9 Misfire Detected

My question to you guys is which should I start tackling first just to eliminate or is there any specific order these should be addressed? Also what are your guys thoughts on why the car is reacting like it is based on these symptoms and codes provided? What do you guys think is causing the misfires and weak engine power?

Thank you

 

Coil or Transformer first, misfires all on one bank are usually ignition related on the V12s. The other codes may clear up if the engine runs properly, but hard to say. Proper diagnostics are key to avoid throwing parts at it, which gets quite expensive.

 

Thanks for the quick reply Joe, what are your thoughts on removing the coil from the non failing side and testing it out on the misfiring side? and also can you elaborate a bit more on what the transformer is exaclty?

Thanks

 

You can't swap the coils, they are mirrored and only fit on one side. The transformer is the square module on the center/top of the engine that supplies high voltage to the coils, it can have a bank fail internally and then you lose that entire side of the engine.

You can get loaner parts from www.v12icpack.com I think it is, to test and see if that solves your issue, then pay for them.

 

 

@italianjoe1 I finally got the car out of the shop yesterday from all the codes mentioned above that we discussed, I changed the Voltage transformer that I bought from v12icpack! great program they have with renting these parts. So I rented the coil pack for the misfires originally and that didn't fix the misfires from all of the side of the misfires so then I rented the voltage transformer and that did the trick. We also replace the TPS.

Car is now runnning WAYYYY better has power when driving compare to when it was in limp mode. After the shop I took it for a drive stepped on the gas and check engine light came back up I didnt bother because i figured it would be the CAT code. So I drove to a exhaust shop to install straight pipes on my v12. Muffler shop took out the mufflers, resonators, and the cats. **THEY DIDNT take out the cats with the sensors** when taking the cats out a bunch of black residue pieces from it start to come out of the old pipes. The guys of the muffler shop said the cats needed to be replaced they said that the black charcoal pieces were the burned filter from the cats and that it was starting to clog the system. So i told them that i would change them soon but not today. I left shop car runs good and sounds amazing.

After 2 days out of the shop check engine light is still on so I went to autozone to check what codes are still there as the mechanic told me that only the CAT code should be the only one. Well turns out I have the following codes:

P0300 Multiple/Random Misfire Detected
P0307 Cylinder 7 Misfire Detected
P0310 Cylinder 10 Misfire Detected
P1422 BLANK
P0422 Main Catalyst Efficiency Below Threshold (Bank 1)
P0300 Multiple/Random Misfire Detected
P0307 Cylinder 7 Misfire Detected
P0310 Cylinder 10 Misfire Detected
P0306 Cylinder 6 Misfire Detected

My question to you guys is what should I do about those black pieces that were coming out of the exhaust? is it the cats? also what are your thoughts on these misfires? OHH and now the battery dies so IDK what I should do first?

could it be that the battery is affecting the misfires mentioned above?

Please give me some pointers!!! AS always your guys time is GOLD!!!