The other day while i was at work (saturday) i went to adjust some things on my programmer (superchips) on my 2003 GMC (4.8L). All I did was adjust the shift pressure and shift points. The I started it up after it was done installing the mods and all of a sudden after I put it in gear and drove like 50 feet, it died. I've had my programmer on for almost a year and have never had any problems with it. So I changed my fuel filter and put some injector cleaner in the gas tank. Nothing. Still does it. It also does it while i'm driving at low rpm's (around 1000) and slow speeds (10 or slower). Could my fuel pump be going out? Any help would be greatly appreciated.

 

Is the theft light going crazy?
Is there any DTC's (diagnostic trouble codes)
If you want you can PM me and I will help with what I can.
Stay Tuned!!!
Ron

 

Did you let it idle for 10 minutes or so to let it re learn the idle? Just an idea. You could try putting it back to stock program try it and see, then maybe go back to programmer tune and see. I think you can go from there...

 

Try the simple stuff first, Could be the plugs. It happned to me once, my front 02's were out for a good while and the carbon build up just killed the engine one day while i was driving; Changed the plugs and she ran like new.

I believe the fuel pump wont sputter the fuel like that, its dead and does nothing or it works; i may be wrong though.

 

it was the throttle body. i talked to my local gm dealership to one of the techs and he said to clean out the throttle body. I took a can of throttle body cleaner, opened the throttle body butterfly, cleaned it out and it worked....