M3RC3D3SE55AMG

Dear MBWorld Members,

I have another ongoing thread about my car, but I'm starting this one to ask for help and advice on a specific issue. My car has developed a serious misfire over 3000-3500rpm and goes in to limp mode due to it. The misfires and limp mode occurring also gives the car an awfully lumpy idle which shakes the entire car.

All goes away when turning shutting off the car/ignition and restarting, only for the same problem to occur over and over again when hitting the said rpm range.

Misfires are occurring on random cylinders, showing the following codes:

P0300
P0301
P0302
P0303
P0304
P0305
P0307

In attempts to remedy the misfires, the following parts have been changed to no affect:

MAF sensor
Spark Plugs
Ignition Leads
Ignition Coils
O2 sensors

Taking into consideration the above mentioned parts have been changed, what else could the misfires possibly be caused by?

Any assistance with this would be greatly appreciated!

I thought it important to mention my W210 E55 is running the 2.0 ECU, custom Kleemann tune, Kleemann supercharger, and Kleemann long tube headers. I don't know if that is relevant but thought to mention it in case it affects any diagnosis.

mufc

your catalytic converters are blocked

M3RC3D3SE55AMG

I'd agree that could be an option if I was running cats, but I'm not. I should have mentioned that in the original post actually. My apologies!

Any other ideas?

Plutoe

I would get the car compression tested---all cylinders!!

M3RC3D3SE55AMG

I'll get to that tomorrow and update the thread with the numbers.

We're going to recheck the air/fuel ratios, injector cycles, and MAF voltage too.

Thank you for your feedback! If you have any other suggestions as well, please do let me know!

mufc

The only other thing I can think of is a lean mixture due to an air leak or a stuck egr valve. Smoke test would eliminate the air leak, EGR should throw a code. Plugged fuel filter ? Weak fuel pump maybe

M3RC3D3SE55AMG

I'm just on my way to the garage now, and we're going to be running tests for yours and everyone else's suggestions today.

I'll post running updates, but most likely in the project thread.

I will of course keep and eye open here for more suggestions and respond with outcomes.

Thank you so much for your time MUFC!

M3RC3D3SE55AMG

A possible "Problem Solved" is on the cards here.

Reverting back to my project thread for further updates. You can check out today's findings for the misfire in it:

https://mbworld.org/forums/w210-amg/...g-project.html