I have a 2001 z28 w/6 spd. 109k on it. Recently started to surge during normal acceleration. Most noticeable in 1-4 gears because of slower speeds. Service engine light flashes sometimes, but can not get any machine to read a code. SES light doesn't stay on and only flashes during highway cruising in sixth gear. Any suggestions.

 

Flashing SES = misfires detected

What's done to the car?

 

Tune, PCM for less, headers back, o2 sims, whisper lid, plugs, wires

 

I'd double check to make sure everything is snugged down right, no leaks (intake and exhaust side), etc. Make sure your MAF is clean and O2's are working properly. If you can't trace it mechanically...then, I'd call PCM for Less and let them know what's going on.

 

MAF looks clean, everything is tight, no leaks from what I can tell. No exhaust leaks that I can hear. I have an off road y pipe. The two o2 sensors that are left, if they went bad wouldn't it throw a code?

 

Assuming PCM for Less didn't kill the codes....

 

Fuel pump and/or fuel filter?

Check filter first for not being able to pass the proper amount of fuel to satisfy the demand of the injectors.