Alright I sold my 1996 A4 this evening (I am getting a newer one) and the buyer just called me, by the time he got home the CEL turned on!!! Because I am trying to help and don't want to screw the guy over, I thought I would post some questions here to see if I could help the guy.

There were a couple of things that I knew were "wrong" with the car when I sold it:

-sounded like there might be a small hole in the muffler, it is a little loud and a cery small puttering.
-Every now and then the Catalytic Converters would rattle (I don't think that they were in horrible shape but...)
-there was a small leak in the basin for engine coolant (it may be that I need a new cap)

These are the things that I knew about that being said does anyone have any guesses as to why the CEL went on two hours after I sold the car? Could it be one of these three things?

The car is a 1996 A4 Quattro and it has 134,000 miles on it. Thanks for the help.

 

tell him to take the car to autozone and borrow the CEL tool. plug the tool in to get the CEL code. that should tell a little bit more about this problem.
the tool plugs in under the steering column towards the left.

 

I got the same problem, use the OBD to test it, and showed the cat is the problem.

However, fully test again, and nothing is wrong is the car. weird........

 

If you filled the gas tank before u sold it, maybe u didnt close the lid all the way. I had that happen to me and had to restart the ECU. Just a thought....

 

It could be litterally hundreds of things. Only way to know is to get the car scanned for the fault code causing the CEL.

 

Tell him WELCOME to the Audi family!!! These guys have some good input tho....

 

so sad [>:]

 

does autozone charge to use their computer tool? and if so how much?

 

Every VW/Audi owner needs a cheapo OBD-II scanner, to keep in the glovebox. I paid $60 for mine, and it already helped me diagnose a vacuum leak in the Passat.

 

does autozone charge to use their computer tool? and if so how much?