renopor

hi all, im at my wits end with my w211 e240, it had multple misfires and a problem with goin past 4500 rpm. ive solved the multple misfires with new coils, plugs and a new MAF. but its still have the misfire at 4500 rpm. under hard acceleration the and above 4000 rpm it starts to misfire and continues to do so till i pull in and turn the car off and on again. it throws up an engine check light everytime, and when i plug the car in it shows up a misfire on cylinder 4. i have charged coils and leads etc around and its still shows up cylinder 4. i have also now changed the cats, but the problem is still there. the car drive perfect and it will drive car the way in every gear to any speed once you dont gun it hard. any ideas where to look next? ive done a compression test on all cylinders and there all perfect, and all sparks have been changed.

195910

Your mechanic should go through all the actual values for this cylinder:

- Ignition angle.
- Injector timing.
- combustion time.
- Knock sensor (ignition retarding)

With all the parts you've replaced. I suspect a faulty injector/ fuel delivery, Have the mechanic switch the injectors to see if the misfire moves to another cylinder.

renopor

right, just switched around the injectors, put number 4 (which is showing the misfire code p0304) with number 1, and the misfore on 4 is still there! dont know where to go next with this so any help would be greatly appreciated. no matter what i do the sec you drive it hard it above 4000 rpm it turn on the engine check light and drive lumpy till switched off and on again. cant figure it out.

195910

Any Other Codes showing? remember to clear all the faults codes after every attempt.

Have you monitored the Actual values?

Please provide the VIN number if possible.

Its a B**** of a problem, But hang in there..

renopor

no, no other codes at all, just p0300 on cylinder 4. ive cleared the codes everytime, engine check light goes out, then bring it for a short blast and light comes back on and she runs lumpy again. every shows up fine on actual values. freeze frames are between 4500 and 4850 rpms but nothing usual shows up.

195910

The documentation states that this might be related to afew things:

1 - Injectors, Perform the Injector tests (monitor cylinder 4)

2 - fuel related:have you had any work done on the fuel pump/line/rail/filter ?
If so, please states them.

3 - Read the adaptation values for each cylinder and observe high deviations in cylinder 4. reset and perform self adaptation.

4 - If you've replaced the ignition coils (its actually stated as NOT a remedy), test the ignition module.

5 - Check function of crank position sensor (also visually inspect)

6 - Check Fuel Pressure and capacity.

195910

Just to mention one more point:

- It is recommended to Perform a fuel system bleed and filter change.
Its a remedy for a few Misfire cases on the M112.

renopor

Hi heres the VIN number - WDB2110612A106038

195910

Any updates on that E240?

big_mike1979

bro, i got the same prob in my 320clk.. misfire cyclinder 5 and i have done everything that u did.
above 4500 rpm, it misfire.
heading to the dealer on monday at 9 am.

ap10046

I know this is an old post, but I am currently experiencing the EXACT same problem on my E240!!
Check your O2 sensor on the cats...I have added an H pipe and removed my secondary cats and resonator and the problem started IMMEDIATELY after.
My car is going into the shop for this today.

Davie500sl

Hope you got yours sorted, exactly the same with mine but showing cylinder 1, replaced plugs, MB leads coil packs air mass, runs great but still the misfire. Turns out it has variable pressure in the inlet manifold, and is losing water. About to remove the head and have a look will post results soon