Audi A4 mal function check light

My "Mal function check" light came on and stayed on when I started the engine. Any one know what kind of problems would caused that light to
turn on? What's the average cost for performing the OBD reading? (on board diagnositc system) Thanks every one. Hunter
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*Lots* of data feeds the Readiness Codes - at least one of which ain't ready in your case. It could be something as simple as a loose or faulty fuel tank cap (hint hint).
Reading the Readiness Code takes all of a minute. Probing deeper into the ECU to dump error data takes a couple of minutes more. Fixing what is found takes the real time. I have no idea how much a shop charges for this - I use my bought copy of VAG-COM on my laptop to do that...
/daytripper '00 s4 6spd
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I had a similar problem about a year ago. The light came on and stayed but there was no detectable loss in engine performance. Turned out it was the catalytic converter which, fortunately, was still under warrenty.
Doug

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My light came on last week, first time in 2 years. Chucked the Vag-com on and it was getting a low reading on MAF, looked under the engine and noticed the hose from the inlet manifold had broken, looks like a bad design, so i just cut some of and re attached it, job done... :) reset code in 2 mins and im on my way
1.8tq
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that needs attention immediately. If the light is just on staedily, then it could be due to simply a random event like a brief misfire. In such a case, if the problem does not recur, the light will usually go off by itself after several days in which case there is no need to do anything. You can probably drive it for a few days to see if that happens before taking it in for service. Also make sure to check the gas cap is on properly.
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wrote:

Autozone will read the codes for free ... when my CEL came on, it was the gas cap on one occasion and the temperature sensor on another occasion.
2001 A4 2.8L V6 (84,000 miles)
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