Reduced engine power on 2006 Chevrolet Silverado 2500 HD

While driving the truck will go to reduced engine power. I can stop, turn the key off and restart within a few seconds. It will then run fine, sometimes for a few miles, sometimes for weeks. Some times it will clear the engine hours, sometimes it won't. Also sometimes the check engine light will come on, sometimes it does not. What could be the cause of this? I have not had the codes read yet.

by in Silsbee, TX on February 05, 2013
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3 answers 5 comments
ANSWER by , November 18, 2015
I have an '02 Silverado 2500 HD 6.0L, that has been giving me the same problem. Started out small, then steadily increased until yesterday, when the stupid thing finally threw codes PO171 and PO174. System Running Lean Bank 1, and Bank 2. http://repairpal.com/OBD-II-Code-P0171-and-P0174 My problem is a vacuum leak, and I finally found it on the air intake, right after the MAP sensor, where the rubber meets the plastic. Apparently, the intake was touching the engine, and slowly melted a flat spot on the underside. Good luck.
COMMENT by , November 18, 2015
I brought the truck to a shop and they replaced the throttle body. All is well again. The truck has more power now than I ever remember it having.
COMMENT by , November 18, 2015
What was the issue with the throttle body? I'm curious to know which components were at fault. And why, because if fixing my vacuum leak doesn't work, I'll be looking there next. =/
COMMENT by , November 18, 2015
I think the mechanic said it wasn't sensing something right. I don't remember for sure, that was over a year ago. I just know he said he replaced the throttle body itself.
ANSWER by , February 05, 2013
have it scan tested for codes and check your fuel pressure
COMMENT by , August 08, 2013
have replaced the camshaft ,crankshaft sensors , just replaced the fuel pressure regulator ,still will not accelerate .have to push so very easy to get go. it takes a while to get too top speed.if you mash the gas too hard sometimes you have to start all over again .
COMMENT by , November 18, 2015
http://repairpal.com/OBD-II-Code-P0171-and-P0174
ANSWER by , February 06, 2013
agree with good guy