Service Engine Light..AGAIN

[GMCJIMMY]

My wife has a 2001 GMC Jimmy that continues to have the Service Engine Light come on.
We bought the Jimmy new, and have had it back to the dealer 6 times for the same problem.
Each time they claim they fixed the problem, but it continues to recur.

Example, one time they suggested to my wife that she was fueling the vehicle with it running. (But they did reset the light).
Each time after that they have said it has been emission problems.

This is our first vehicle that we have had this kind of problem with. The 3 year warranty is up in 2 months (we bought it late 2001).

Any ideas on what it may be, since the dealer can't figure it out, and our warranty is about out?

[GMCTech]

If you could find out what codes were being set we may be able to help a little more.

There are a number of different possibilities.

If the vehicle has had the same code(s) over and over again withou the dealer being able to fix it, you may need to find another dealer that knows how to diagnose emissions issues. My guess is that the codes are EVAP or A.I.R. related issues and they don't know what steps to diagnose properly (even though they have all the service information and diagnostic trouble trees and charts.

Hope we can help - just get us a little more info if you can.