I have a 1996 C280 and when I start the car if it is not already warm it will idle to 3000rpm and then die out - after another start the car will idle high and stay on. When at a stop light or sign the brakes are heavy and it's as if the slightly higher idle is still letting fuel flow through the injectors and trying to keep the car moving??

I have replaced the Air Mass Sensor and was wondering would I have to reset the computer by taking the negative lead off of the battery for thirty minutes??? Also if I have an newer radio - I don't think that I would have to use a radio code???

Any help would be appreciated???