hello,

my stock 5.3 with 90k miles seem to "knock" or loss a beat when ever it's hot and idling, i can fell the engine shack a lil and the rpm drop a lil to.

on my aeroforce gauge the timing goes crazy @ ideal jumping from 17* to 22*, also lately i've feeling a loss in power over the power band.

stock 5.3 with specter intake, and no relation to the IAT, cold or hot it doesn't matter.

drive fine, don't smoke or anything

help?

 

Sounds almost more like a miss. Have you tried giving it a tuneup? That or run a few tanks of higher octane fuel through it and see if the problem goes away.

 

New plugs and wires, new specter CAI, always running 91oct. now you mention it i've noticed an increase of the "sot" or black smoke residue on the tail pipe..

 

Is your check engine light on? It sound like it might be running rich and the computer is trying to correct it. You could have a leaking injector. Try running an injector cleaner like gumout?

 

no, and i went to a tuner and HP tuner said i have knock on piston#1, but i cant hear anything and the car run and drive normally.

in 2weeks i'm gonna install AEM wideband and see how things are doing.