Hello all,
I have been having trouble tuning the idle in a friends vette with a 402. For some reason i just cant get the long term and short term idle correction pids to validate to do the rafig process. I have read till my eyes bleed. I have tried validating pids while connected to the vehicle. I can log the idle airflow correction, but that wont do any good without the short and long terms to factor into it. The car runs good other than idle, and sometimes wants to die on a rev. This is the first dbw car i have messed with. Really the only car i have done this much to. We started from scratch on a stock tune. The mail order tune he had was garbage. Can anybody shed some light on how to get this pids to validate?? I will try it on my car as soon as i can (98 t/a with a 402) just to see if they are valid on that system.

Thank you for any help, go easy i am a mechanic, not so much a computer guy.