Hey everyone, I just joined this site in search of some help. I have an '06 sierra denali which is not under warranty as it was a wrecked rebuild. At certain times, I dont have any power. When I give the engine gas, my RPM's rev but I don't have any acceleration (0-60 time is around 16 seconds), and it is sometimes very hard to get it past 60 mph. Most of the time if I shut the engine off, start it up, shut it off again, and restart, it will run fine after that. (Most of the time it also seems to run fine again if it has been sitting off for more than 15 minutes). It is really hard to explain the symptoms, but the truck will downshift like it is supposed to, it just doesn't take me anywhere. This first happened a couple of months ago just a few times, but now it is occuring on a daily basis. There are also no codes thrown and I had it scanned while it was acting up and nothing showed. I cleaned my MAF sensor and it didnt happen for 2 days but is now reoccuring. Could the MAF sensor be shot? Any help is appreciated as I don't know where to look anymore. Thanks

 

maf could be the culprit, but check the simple/cheaper things first.
when was your last tune-up(fuel filter/fuel sock on fuel pump intake, spark plugs/wires/coils, and air filter) look at those things first then have your maf checked (a friendly guy with HPT for your truck would be cheaper then the dealer)

 

it sounds like a tranny slip

 

I bet your cats are stopped up.... the 06 will not have a fuel filter

 

DBW(drive by wire)...sometimes it'll exhibit the same probs. you're describing.