W210 surge/idle problem
 

Wife's car is starting to show signs of running at speed and when stopped of some fuel starving problems. I know the obvious of replacement of fuel filter, but what about the injectors.

How would I go about cleaning these or do I put in some %^& in the tank to resolve this? I know this is hard to diagnose here on the forum with words.

Any other signs of trouble, like the check engine light?
Gilly

No check engine light is on.

The other day we were on a beach drive and it slowed to a stop light. It went why below normal, like it wanted to die and the ASR light came up but then disappeared when the revs went back to normal.

My wife claims she can be driving at 80 and it will just kind of lose power then rise to the occasion again, however, concerning her enough to move to the right lane in case it would die.

Since it's an M119 motor, I would suspect it's the throttle actuator going bad.
See if a shop can fish out that code in the ASR system though. edit, have them check for codes inthe ECM too..
Gilly

Isn't the throttle actuator supposed to last the life of the car??

Are there going to be codes even though no idiot lights are on?

No and yes, respectively.
Gilly

Turned out to be the Air Mass sensor!!! According to the codes. It also may be needing the knock sensor replaced but I am going to see if when I replace the air mass sensor if the code for the knock sensor goes away. Otherwise, it will be replaced as well.