Hi all, have a question. I have vintage air gen4 setup for my Ls3 motor (using front runner so their compressor). What happens is when AC is on and I come to a stop light or stop sign the car dies. Always thought the Drive by wire would pick up the need for extra idle speed and detect this. What am I missing? The motor is the 430hp FI crate engine from Summit with the stock GM wiring harness. Thanks for any help!

 

Find a custom tuning shop near you and get a custom tune done on the pcm and there are a ton of tables they can alter to address your specific issue. Not a uncommon issue with the canned tune gm uses in their pcm's for crate motors.

 

Sounds like you could cure with a custom tune or maybe add an idle speed control unit that will bump the idle when the a/c comes on

 

Ditto from above. What did you install it in?