Hi all

I have a '99 CLK 230 Komp Auto.

When I rev my car hard it loses power and runs lumpy like its on 3 cylinders.
If I stop, turn it off then restart it runs smooth.

??????????? any suggestions

 

You should get the check engine light On with each ocasion. Have autozone scan the car for trouble codes. Same symptoms are common on 320 engine when crankshaft position sensor is faulty. Code P0300 to P030X would be misfire and computer will shut down fuel injector and ignition coil for those cylinders untill you turn off the car and restart it again. Usually anything above 4000 RPM will trigger your computer to let you know about more misfires then allowed per each 1000 RPM.
I was blaming spark plugs, wires, coils and even injectors but now I would first replace the CPS before anything else.

 

No warning lights at all......

Just ordered a replacement MAF (mass airflow thingy)

I will change that when it arrives and see how I get on.
If there is no change I will try your recommendation!

Regards

 

Please let us know later if the new MAF sensor took care of your problem.

 

Will Do!

 

Put the new MAF on today...
Ten minute job, £35 off ebay.
Its like a new car, much more responsive and its solved the original problem of hitting a brick wall on revs and running lumpy!!!

Chuffed to bits!!!