Mercedes C240 Problems

You have replaced the YAW sensor. Have you replaced the PITCH and ROLL sensors?

We do not have ESP, ya know.

_{^{(Sorry, lanney. Not picking on you, just having a little fun with you. You'll get used to it!)}}

No, I am going to try to change the MAF sensor. Another C240 owner had a similar problems (car shudders @ 3200 RPM) Will try a "Junk Yard."

There are at least two gentlemen that are more familiar with Mercedes that are regulars at this website. If they can't come up with something that can help you we'll give it a shot, but there is no substitute for good experience.

h

try this link re mercedes previous postings

http://cr4.globalspec.com/search/sitesearch?do=show&sort=textmatchrank&srch=mercedes&order=asc

i take it its a fuel injected engine ?

are there any error codes stored on the ecu ?

reason i ask its possible that no 6 injector is failing.

so when revs reach a certain point the cylinder is missing the ECU picks this up and turns no 6 off hence the misfire, then car goes into limp home mode to protect itself.

YAW sensor is part of the stability control system and MAF is fuel management.

I can't help you, but this sounds like two different problems.

I am not one of the two gentlemen to whom Guest referred.

Sorry , but you were one of the two to whom I was referring. You know what this means now I have to give it a shot unless Peter's suggestions direct him to the possible solution. A shot is about 1 oz. isn't it?

h

Thanks.

You will find this very interesting:

http://cr4.globalspec.com/comment/577746/Re-Mercedes-W124-Unstable-Engine-Idling

one i made earlier

http://cr4.globalspec.com/thread/55566/Mercedes-W124-Unstable-Engine-Idling#comment577523

So you did...okie—dokie

If the misfire is from cyl #6, and only at above 4,000, I would save some money, and do some substitutions first. I think the easiest thing to do is move the coil to another cylinder. Drive above the 4,000 threshold, and see if the light comes back on. If so read the code. If it is still #6, the coil was not the cause. Next try the spark plug. Same test. Next the plug wire. By using components from different cylinders for testing, and noting where they came from, you can do all the tests at once. That will avoid paying four times for the reading of the codes if you do not have access to a reader. ( Coil from #1, plug from #2, wire from #3, and injector from #4.) Although the coil fires two cylinders (I think) it could still have a breakdown problem that only affects one cylinder. My personal guess is the injector. I think other components would recover as soon as the car is below the 4g threshold. But an injector might not. Only you will have that answer. Good luck.

My mechanic switched everything from the number #3 cylinder to the #6 and the same thing happens. He also says that it wasn't the fuel injector. I might have to take it straight to the dealer if we do not come up with another solution soon. We changed the fuel filter and the car is driving better than before, except for the 4000 RPM problem. I am totally frustrated.

this may sound silly but is there any way you can check to see if there is a blockage in the inlet port going to no 6 cylinder ?

firing order

http://www.justanswer.com/questions/2flyv-what-is-the-firing-order-of-the-2003-mercedes-c240-and-what

Is your engine a V or inline ?

injector faults

http://www.carsuk.net/mercedes-blueefficiency-om651-injector-problems/

misfire at 4000 rpm.

http://www.google.co.uk/search?q=Mercedes+C240+Problems+miss+fire+at+4000+rpm&sourceid=ie7&rls=com.microsoft:en-gb:IE-SearchBox&ie=&oe=&rlz=1I7GZEU_en&redir_esc=&ei=yoUfTPnGBYv40wSGocWiDQ

and

http://www.google.co.uk/search?q=Mercedes+C240+Problems+miss+fire+at+4000+rpm&sourceid=ie7&rls=com.microsoft:en-gb:IE-SearchBox&ie=&oe=&rlz=1I7GZEU_en&redir_esc=&ei=yoUfTPnGBYv40wSGocWiDQ

Once the car exibits the 4g problem, how do you correct it again?

By the way, welcome to the insanity.

Thank U.. at least I know that I am not alone.