hi, check out the air mass flow meter this is what takes the place of the carburator if that makes sense. in other terms it lets X amount of air all the while measuring how much gas to inject into with that air
that meter may become stuck and this is why it happens a lot at times of decreasing rpms (how fast your engine is traveling) if you have a tach (measure engine) you can see at what conditions this happens. what i suspect is there is some plastic interfereing with the gradual decrease ing the meters motion i aint any sort of expert and use your own gudgement on this but if you are curious to thest this hypothisis trace the air tubes from your air filter/cleaner till you get to the meter (large metal has electronics hooked up to it) it is ok to unhook the elecronics to get a look at the sensor- be gentle around the sensor it may have a thin metal screen that you dont want to puncture - bottem line i think the door which opens according to how much air is needed is geting hug up on some piece of metal or plastic which shouldnt be there (not a do it yourself deal) but it is a warenty deal take the car in for a check up before you dismantle i would like to here what it was sorry i ramble on to much
D class
May 2006
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