QuestionQUESTION: Hi, I have an 1997 audi a6 2.4, i have 2 questions. Firstly the car at idle is jumping up and down between 300rpm and 600rpm which is to low and keeps stalling. I am led to believe this might be caused by the tps, maf, idle control valve, ect or evap circuit. Please let me know which of these it is most likely to be. Secondly i have 2 lights that stay on the dash at all times which are for The abs and esp, what would cause these lights to stay on. Thanks heaps Jeremy
ANSWER: The idle control module would be my first check; this often gets dirty which will cause it to stick. For the second problem I would check the wheel sensors, since both of those systems (ABS and ESP) rely on wheel rotation sensors, and one is linked to braking while the other is linked to acceleration. The wheel sensors are common, so to check the wheel sesnors (and the wires to them) you will need to take the wheel off, disconnect the connector to the sensor, connect a voltmeter across the sesnor and spin the wheel. If the sensor is good you will see small fluctuations on the voltmeter. If you find one that does nothing, then that one will need to be replaced, and these little suckers can get really tight in the castings, so may need some persuasion to remove. Good luck, Jan
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QUESTION: Thanks for the advice it is much appreciated. Please excuse my lack of knowledge but this is the first European car we have owned, Where would i find the idle control module and can i just clean it with some carbie cleaner or something along those lines. The wheel sensors were my thoughts to but i wouldn't have know how to check, thanks for the advice again in advance.
Yours gratefully Jeremy
AnswerHi, the idle control valve is attached to the air inlet in front of the throttle control and typically also has some electrical wires going to it, as well as two or three 3/4 inch tubes. Yes it can be cleaned out with carburetter cleaner. Good luck, Jan
