The check engine lamp is illuminated in my '02 Suburban. It has the 5.3 2wd. The FLAP said it's a hi-lo voltage(?) reading from the E85 sensor. Since there's no E85 here, and a new sensor is $300+, a friend said I could have the computer or chip re-flashed to get rid of the E85 portion. The Sub will also have to pass a state inspection before I can use it, so it sits until then!

I have a '95 Suburban 6.5 TD into which I had a new chip installed. It was very simple once I pulled the glove box and removed the computer cover/lid. This fellow only does diesels. He said the '02 will need a similar upgrade