1994 Audi A6 2.0 idling too high

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Mon 5 Jul 2004 21:46
1994 Audi A6 2.0 idling too high - ammo
As the golf is off road, one of my friend has give me their audi as its surplus to requirements. Approx 1 week ago, the car refused to start up. My neighbour who was passing by walking his dog, mentioned kindly "the car always sounds like its only firing on one cylinder" and suggested i should get some new plugs. I took his advice, inspected the spark plugs only to find they were coated in heavy black soot. I replaced them with new spark plugs, only to discover the engine now idles at the 2500rpm. I have checked i bought the right spark plugs, I even checked with Audi-uk to confirm the model and engine size. It has been mentioned to me the engine is running far too lean??? Any ideas.
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Mon 5 Jul 2004 23:18
1994 Audi A6 2.0 idling too high - Aprilia
Sounds like its too rich, not too lean. Enrichment is controlled by the ECU. Could be a duff coolant sensor (ECU thinks its freezing cold and adds extra fuel). Sensor should have resistance of about 2500 Ohms at 20 deg. C and about 200 Ohms at 100 deg. C.
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Wed 7 Jul 2004 17:43
1994 Audi A6 2.0 idling too high - mak
I agree with Aprilia. Is this the ABK engine? You may have two coolant sensors, one for the ECU (blue square on my Audi 80) and a white round three pin for the temperature guage. You may need to replace the blue one. Is the exhaust tail pipe sooty as this would confirm that you are running to rich?
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