Mercedes Benz C240

mercedes-benz
c-class

#1

Everytime I come to a stop, the car seems to be gasping for breath and attempt to want to stall. Occassionally the battery/alternator light comes up. It has not stalled yet and seems to catch its breath and continues once I step on the gas after the shake and after there was an air rush through the vents (I called-Caching its breath). I took it in to the dealer and the electricel was checked and they found nothing. Please help!!. Thanks


#2

Have they checked to make sure its not the torque converter lock up not sticking? Are you up to date on the transmission maintenance, i.e. ATF changes?


#3

I think the alternator/battery light is coming on because the rpm is so low the car thinks it is about to stop. That probably isn’t a clue. Is the check engine light on? Did the dealer read the current and pending DTC’s? When a engine isn’t running well like this, it almost always comes down to a problem in the following

  • Spark
  • Air/fuel mixture
  • Timing
  • Compression

Your symptoms are not specific enough to tell where to start, so probably start from the top and work down.


#4

The info on the car is too scant and the complaint too murky to make any kind of reasonably accurate guess but this problem could be related to a vacuum leak or Idle Air Control valve issue.

It’s difficult to determine if the battery light is coming on because of an electrical problem or simply because the idle RPMs are dropping too low.


#5

No IAC valve on this car

It has an electronic throttle


#6

But a thorough check of all the vacuum hoses would be in order.


#7

Yeah, the check engine light do not come up. The symptons are just the vibration sign of wanting to stop, the rush of air through the vents like it receives more power, occassionally the alternator/battery light. It usually also happens when i slow down to come to a stop or when I speed up and stop there after. It has actually stopped on me once and start right up as soon as I start it again.