after getting tuned (HPT) i have noticed my engine surge when idle at stop lights. I can also see this surge on my AEM air/fuel gauge and it spikes to max 16/17 or goes blank...then maybe 10-15 seconds after it calms down and engine feels normal again and the gauge goes back to 14/15 where it should be.

At first I thought it was a dirty maf, it was cleaned but the issue remains. I then thought maybe it was the tune itself but I have been retuned by 3 different people and all resulting in the same "surge".

Anyone else have this issue? will this harm the engine at all? any ideas on what else to check?

Its a 2008 2.2 auto with approx 70,000miles / 114,000kms, other mods are listed in my sig below

 

Where is your A/F gauge connected? Is it connected to the O2 sensor wires? I know you didn't report a check eng light but perhaps one of your O2 sensors is starting to go bad.

 

the a/f gauge is hooked up to the o2 sensor. bosch sensor comes with the AEM kit.

no engine light on

if i give it a bit of gas during the surge, it corrects itself and runs normal again

 

had someone run my tune and they stated this "I was showing 0-40* of timing at idle while the car surged!"

he ran it on his 2.2 cobalt