After a long (200 mile) drive CEL on my 2000 S430 with 107000 miles came on and stayed on. After another 50 miles the engine started misfiring, and got bad enopugh where the car needed to be towed.

My mechanic (with 18 years of experience in MB dealerships) is stumped. The whole bank of cylinders on the drivers side is not firing. Fuel system checks out, spark plugs and lines check out, coil, etc. His next step is a compression test fearing maybe the timing chain jumped.

He has not seen this before on this engine.

Anyone have any thoughts?

 

For anyone interested, the problem was a "plugged" catalytic convertor (left side) which caused back pressure in left bank of cylinders.

Parts: $150.00
Labor: $1,000.00

 

Forced Induction,

Does "gut all of the cats" mean remove or otherwise bypass the catalytic converters? If so would my vehicle pass a smog inspection here is California?

 

Hi JDAISA! I am glad that you fixed you vechile. I am having some what kind like your problem and I need to ask you some questions. Did the PCM on you vechile gives you any code at all. Cuz I have an 95 SL 600 and my left side bank is fired, vechile idling rough, and I am still trying to figure it out what cuz causing....If you can give me some advice I would be very appreciated. thank You!

 

Smoothride

The codes were not helpful (random misfiring). My mechanic started with the basics, spark plug lines, fuel injectors, spark plugs. Then checked compression which was good. Not sure how he figured it was he catalytic converter but he showed me that the material inside had simply crumbled and was blocking the exhaust flow causing back pressure into the left bank of cylinders. Seems to be an easy check though, just a few bolts, but I am not a mechanic. Sorry if this wasn't helpful.

JDaisa