Ronny

iTrader: (1)

i had issues with idle quality a while back. one of the things i tried was to set IAC steps to zero 148d C through 71 d C. at 63 d C it is 5. idle commanded to 700 rpm. then i set idle manually with throttle stop screw to 800. open loop A/F idle is 13.5-13.7-13.7 when at running temp. i left as is and ran OL and that is improved. idles today 900 rpms OL and steady. when fully heat soaked(manifold) it runs 900-1000. occasionally hangs 1100 but comes down eventually. so much better but not perfect.

i just saw a post(JP) that suggests that certain (above) IAC commanded steps will not allow idle to come down? please elaborate.

is there apossibility i cannot close off anymore inlet air as i think stop screw is barely touching throttle stop. TPS is .59 V. is the air moving around the Bflys (2.00 in) and unable to be reduced due to clearances Bfly/sidewall.

dimented24x7

iTrader: (2)

Its been awhile, but in order for the engine to enter closed loop idle, the IAC steps in the IAC steps vs. coolant table must be less then or equal to the kickdown steps, which is something like 65 stock. At low temps you want to have the IAC open some (more counts) so the engine runs properly when cold but at operating temps you want it to enter closed loop. So, you enter values equal to or less then the kickdown steps so the ECM will allow closed loop idle.

As far as the high idle, you may be SOL if the TB is allowing too much air to pass through. The IAC will basically be shut all the time at idle.