2007 silverado reduced engine power

2007.5 Silverado lmm with engine reduced power no codes. This first happened after filling fuel tank. Changed fuel filters stock and the two fass filters.
I dropped the tank cleaned it new fuel replaced fuel pick up(broke taking it off)
no joy
I have changed MAS sensor, throttle body, tpp, cleaned all grounds. NO joy.

The symptoms, truck runs fine for about a minute to two then into reduced power, this will happen just idling or running hard.
starts fine, idles fine

any help is much appreciated

Keyes

I would look at the throttle actuated controller wires and TAC unit as most reduced power issues have come from those two areas.

Thanks I have time tomorrow and will do

So, it says Reduced Power on the cluster but has no codes? What kind of scan tool did you use to check for codes?

Is this a gas or diesel truck? I would think there has to be a code stored for this too.

Nissan Technician

For the throttle control actuator more often than not when it acts up it wont throw a code. There is a tsb and recall on this for Chevy and GMC trucks that have this issue. You will need a scope to catch it in the act otherwise call the dealer to see if your truck is covered under the recall. If you do this yourself you will need a scanner that can show live data and graph view for maf, tac, app, tps, and iac. Basically a verus, modis edge, autel etc. That has a scope with it.

That's where I would start. I have replaced several throttle bodies, throttle pedal position sensors, and grounded the controller on a few. If it starts and acts ok after key off for a couple minutes, even if it does it again, it is definitely in tac system

How many miles on this lmm ? Can you hear your fass pump running with key on? Ive had some pumps die and it was a big fuel restriction that would cause reduced power...If you have acces to live data take a look at desired and actual frp also take a look at the tac voltages and % make sure they agree. It should definitely have a code when its in reduces power mode that should help point you in the right direction. On a side not if your fuel filler neck broke I assume your in the rust belt in which case take a look at your fuel lines and fuel cooler I've had tons of these trucks with leaks on the suction side that would allow air in the fuel system causing low frp also the primer bulb on the stock filter housing is another common air leak ,which reminds me was the stock fuel filter changed? I don't remember reading that in the op.. also for anyone following along this is a duramax diesel

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