engine issues on 99 c230k
 

I have engine? issues with my w202 99 c230k. If I step on the accel. more than about half way, the car goes into convulsions! Even worse when it is cold. Then sometimes I think it kicks into limp-home mode. I stop the car, restart it and it goes back to normal, as long as I don't step on too hard! I've had it scanned, and it seems to be missfiring. The mechanic did not know for sure from the scan, but was guessing on a few things. Before I let him guess with my pocketbook, I figured that I would check here to see if anyone has had similar problems, and what the solution was. I changed plugs, wires, coil packs. Did not help...
Any takers on this one??? (oh yeah, 141,000 km or approx 87,000 miles)

Dale

Does the event occur at exactly the same rpm every time? Were there any fault codes stored?

dalrex, hi, i have the same car 7 the same thing happens to me as well.

it seems the only time my car looses accleration is on warm starts. ive learned to warm it up regardless of the weather condition for 5 minutes.

look up my odb2 post (posted today)

let me know what you find!

I haven't noticed if it is the same rpm, but I don't think it is exactly. I will have to check the print out that the mechanic gave me. I know it said something about missfiring. I will let you know when I get the sheet tomorrow...

here are the codes...
 

Here are the codes from the scan, which I believe he ran twice...

P0170 ASELF ADAPTATION/ AT LIMIT (N3/10) 2X, P0300 MISFIRE DETECTED 2X, P0301 MISFIRE #1 2X, P0302 MISFIRE #3 2X, P0370 ANGLE DEVIATION BETWEEN CAM/CRANKSHAFT, P0304 MISFIRE #4......

Any help with that?

bump...

I could be 100% wrong, but that sounds like the MAF sensor to me.

problem solved
 

You were 100% right!! :) Changed the Air Mass Meter (Mass Air Flow sensor) and the car seems to perform better than the day I bought it 3 years ago.
Anyways, thanks for your input. It saved alot of guessing with $$$!
Dale

Exact Same Issue
 

""" If I step on the accel. more than about half way, the car goes into convulsions! Even worse when it is cold. Then sometimes I think it kicks into limp-home mode. I stop the car, restart it and it goes back to normal, as long as I don't step on too hard! I've had it scanned, and it seems to be missfiring. The mechanic did not know for sure from the scan, but was guessing on a few things. Before I let him guess with my pocketbook, I figured that I would check here to see if anyone has had similar problems, and what the solution was. I changed plugs, wires, coil packs. Did not help...
Any takers on this one??? (oh yeah, 141,000 km or approx 87,000 miles)
"""

I have the exact same car. Have a "p0304" ERROR CODE. I already replaced the MAF but am having the same problem.

I am wondering if I am supposed to reset something after I replaced the MAF, or erase the code or what.

From everything I have heard, the MAF should have fixed the problem, so I cannot help but wonder if I missed a step.

PLEASE HELP

P0304 means a misfire on cylinder #4. Doubtful that a MAF would effect only one cylinder. Think secondary ignition, vacuum leak, fuel injector, loss of compression.

I would be suspect of several things causing that misfire code. A common problem on the M111 engine is the plug wire ends, they corrode and cause misfires. I replaced all four of mine at 160K and they were in pretty sad shape. M111's also tend to have leaky valve cover gaskets (A bear to DIY, btw) ands I have seen oil pool in the plug well causing a misfire.

P0304 is not a typical code for AMM.

C230 shudder problem solved
 

I figured it out. I had to replace the plugs and the plug wire ends. Thats all, problem solved. I thought I would have to replace the coil, but learned that it was the plug wire ends that go bad,.