i have a 99 c 230 kompressor recently the rpm's/idol have been higher than before. Looking at the rpms needle it seems like itsreving up thendown then up then it finds its happy medium.It seems to me that that the rpms are too high for it in low gear.Almost like the car isnt shifting.i thought maybe the transmission fluid was low. i took it in to the dealership told them what was going on with it and they did an oil change, new filter and flushed the old transmission fluid out and new in,now it seems the car drives worse. as i come to a stop the cars rpms go up then back down. please someone help!?

 

OK>let me make sure I understand this correctly.....you took the car to the dealership for an erratic idle problem and they changed the oil and filter and tranny fluid and filter to fix it? Hmmmm. Is that what YOU told them to do, or is that what they said would fix the idle problem???
Two very different scenarios in my mind. If it's the latter, then you need to take it right back to them and tell them what they did....did NOT fix the idle problem and they now need to fix it without charging you again. If it was your idea to do a fluid change in hopes that it would cure the idle problem, then that's different. Whenever I have any problems with any car I can't fix myself, and have to go to a dealership, I always tell them to diagnose first, THEN fix what's wrong, nothing else. And let me know what it is after the diagnosis and before the fix so I'll have an idea of not only what it is, but how much the cost will be. This way, if the car still has this problem, you're covered.

 

I am having the same problems!!!! I replaced my air mass sensor and it is still doing the same thing, but just not as bad??

 

Ummmmm, I found out the problem with the car as my C280 was having the same problems - it was a small cheap piece that was causing all the problems!!! A little VACCUM HOSE had a split in it and that controlled the idle of the car, the brakes and the power steering - that might be your problem and all this was found out NOT using a computer????? Too bad that I replaced the MAF sensor first and as you know that is a costly piece of hardware!! This might be your problem??