Check Engine Light Coming on intermittently?

(2012-02-03 15:20:13)

1. Naughtynerd Says: I have a 2003 Chevrolet Silverado HD with the 6.0 Liter engine. Once in awhile the check engine light comes on then my truck starts to run at Reduced Power Output or something to that affect. Then the engine will misfire then the speed drops to going about 35 MPH. I plugged my scanner in and nothing or zilch shows on it. I shut the truck off when it was safe to do so then restarted it. The check engine came on but it was operating at Full power. If it sits for awhile everything seems fine, but now I am nervous about driving it. This is the second time it has happened. Is there anybody out there to help point me in the right direction. Does this mean I will have to purchase a new ECM for the truck? What should I look for in the cost. What else could I do to check the engine on this truck? My scanner does function because I have tried it on other vehicles and it does read codes.

2. matt Says: You should rescan it now that the light is on. The vehicle went into limp mode because a vital sensor died. That check engine light knows which sensor it is. Go get it.