base line tickover

[Prawn]

I have been trying to adjust my base tickover after setting the AFM and TP voltages.

If I block of the pipe to the stepper the tickover doesn't really change, also if I wind in the screw on the plenum to adjust the base tickover it does not have any effect until it is pretty much down on the stop.
Even then it does not get below 700rpm.
If I release the pipe at either this point or with the screw out 2.5 turns my tickover sits at around 850~900 rpm.
Any ideas ?

[Ozstyle]

Hi,
could be that the pipe to the stepper motor is not fully clamped/blocked letting some air passed upsetting the procedure. Also its advisable to reset the ecu afterwards as this does control the stepper motor.

[blitzracing]

Have you caused the throttle buterfly to sit open a fraction when you set the tps ? Take of the air intake to the plenum and have a look, as there should be no gap around it allowing air in. Air must be getting in somewhere into the plenum, but if it does not go through the air flow sensor, the mixture becomes very lean, and it would not tickover smoothly (if at all). Setting the idle mixture does make a considerable difference to the base tickover position.