Originally posted by Tired2Are you on High or Low Z Injectors? I did not buy from symtech, but I believe their guides imply using a pwm idle valve, not a 4 wire stepper like the 420a has stock... you may or may not have the hardware on your board to run the stepper based one. Additionally, it could be open or closed. If you pull the throttle body off, it is easy to see where the valve is in its cycle, but that is a pain. You can block it with a vacuum plug or some-such, just don't let the plug get sucked in the TB :P Some info on Stepper IAC:
I managed to use a trimmed down vacuum plug on the throttle stop to achieve about 7-8% tps when off the throttle. Of course, I disabled all the closed loop idle and such.