Hey guys, having issues with my 03 LB7. I have just rebuilt the entire motor and now i am having problems with the motor throttling up in park and in drive. When the motor is in park the motor will slowly gain power with the pedal mashed to the floor. When the truck is in drive and the pedal to the floor there is no power gain at all. The motor seems to idle fine with no hiccups and it seems to start up every time when cold. The motor has stalled / quit with no warning before and taken a couple minutes to restart with a few pumps of the fuel primer. I have ran the diagnostics on the fuel pump, injectors, fuel regulator, MAF sensor, and the Accelerator Pedal Position Sensor all seem to check out fine. By the way no codes have showed up other than a air intake heater circuit issue that I have yet to fix. So far I am thinking possibly a ECM issue? Sucking in air somewhere in the fuel system? Or possibly a partially broken wire ???? Any help would be great guys !! By the way this site is awsome !! New rookie member as of 04/27/10

 

no codes at all?

this what kind of scan tool do you have?

 

I have a OTC SPX scanner that I ran on the truck, I also had a GM tech stop by with his scanner and still no codes have come up. I did notice that the GM tech had a couple of minor difficulties with trying to make communication with the ECM when he ran his scanner ?