The Malfunction Indicator Light (MIL/Check Engine Light) in my 1997 Audi Quattro Wagon has been triggered. According to the Owner's Manual (Audi A6/A6 quattro, Nordamerika, englisch 7.96, 971.561.4A0.21) on page 67 & 68, two things could be happening. 1) Emission control system malfunction, 2) Speed limiter malfunction.
According to the owners' manual, the on-board diagnostic system should register a code in the control unit's memory if the emissions system has malfunctioned, but the manual does not state if a code will be registered due to a speed limiter malfunction. I have checked for codes with my OBDII code reader (Codekey model 375265 from JS
Products, Inc.) and no codes are detected.
Some background information: Last month, my Audi would die at stop lights, but the MIL was not being triggered and no codes were registered so I had Audi check the car. After they cleaned the ICV (Idle control valve), Throttle pipe and readjusted the throttle switch, the car not only stopped quitting at stop lights, it also performed better and responded with more power. It wasn't until two weeks after Audi fixed the stop light issue that the MIL was illuminated.
Has any one encountered a situation like this, or does anyone know what else would trigger the MIL without registering a code in the control unit's memory?
The car is running great and only has 80K miles on the odometer, but driving around with the MIL illuminated is not very reassuring. Thanks in advance for any light you can shed on the issue.