Chevrolet Repair: colorado moter, circuit failure, code scanner

Question
 I have a 2004 colorado with the 5 cyl   the ck eng light has been on for a while  i have tried scaning the computer but it did not point to the same problem both times i have ckd it. I rember a leter from gmc talking about valve seating problems causeing rough idol and was wandering how common this was and weather it would cause stalling

Answer
Hey Brian,

 What were the exact codes you retrieved.  There is a literal infinite amount of circuit failure variations that can trip the light.  There are problems with valves, rockers pulling out and piston sleeves moving around.  If you are using a generic code scanner it may not be spitting out TCM or BCM codes properly. There is a TSB for valve springs causing missfires but I have not seen one do it yet.  My shop has had a couple of dozen Colorado's in the door and we are replacing u-joints, ignition switches and front end components like crazy.


Wayne