LQ4 Backfires, stumbles on light acceleration?
 

I have had my motor swapped into my Suburban for about 4 years now. Recently when the motor is warmed and I am giving it light acceleration, it will back fire, and stumble a bit. I do not have a check engine light on. When I did the swap 4 years ago, I installed new plugs, wires, and coils.
I am wondering if I should replace the plugs again, maybe the cam and crank sensors?

Re: LQ4 Backfires, stumbles on light acceleration?
 

Put a scanner on it and look at misfire data and if there are any codes. Just because there isn't a check engine light on doesn't mean much, it could have the error reporting turned off in the tune. Crank and Cam sensors aren't likely going to help, and throwing money at it will just be wasting money.