Check Engine Light - I think it's just a gas cap.

[Cowgirl_Jules]

@Joey_P

Is your truck pre 1995? The only truck I’ve seen that did that didn’t have OBDII. It did have a harness for a reader though. I had to jump to or 4 pins in the harness then turn it on and off like 6 or 7 times and it would spit out the code via the CEL.

No, I can do it in either my 2004 or my 2005.

Bearflag, I was browsing the Costco flier at lunch, and they have a code reader at costco.com for about $35, that seems to give you a little more than just the code.

Don’t you just know I can’t find it online. If you want, I’ll look in the flier again when I get home.

[JFLuvly]

OBD11 (On Board Diagnostics) came out in 95 or 96 I think. The problem with the cheap readers is that alot of times they just flash LEDs and you have to count the flashes. This can be a pain in the buttt with multiple faults. Also, I don’t think they are capable of resetting a fault only telling you where the problem is. An EVAP fault is pretty common and I think also deals with the gas cap.