I have a 2002 Suburban with the 5.3 liter vortec and I am having issues with it running rough when cold and the "service engine soon" light coming on periodically for a matter of a day or two, go off again for a while, then coming back again. Can't seem to make up its mind if it happy or not! A buddy of mine has an analyzer and when he plugged it in to check the code it was showing, the analyzer could not find that there was a computer module in the circuit.

Anyone out there know what my issue(s) might be?

I assume that if the computer module was bad or dead, the "service engine soon" light would not light up, or would just stay on? That said, when it is cold it kinda runs like the computer is not controlling the choke or other cold running features correctly. Could it just be a fuse that runs the computer being bad?

At a loss...