Engine/Transmission (1998.5 - 2002) Check Engine Light

[Big P]

I installed my Edge Comp the other day and in the instructions it says turn the ignition to the run position but do not start, and see if the check engine light comes on. Well the light came on but when the truck is running it's not on. So I disconnected the Comp, tried again, and the light was still on. I've had the Comp in for a couple of days now and it runs fine. I did set off a code with a bad map sensor connection a few months ago and I'm guessing that's what it's from, but when I cycle the ignition key 3 times no codes show up. Any idea's

 

[Blu-meanie]

The "Check Engine Light" isn't supposed to be on when running. It only does that when something fails.

 

[Big P]

It's not on when the truck is running. It's on when the key is in the run position while the motor is off. I'm not overly concerned, just was wondering what was up with the light.