Cam surge - Pointers to tuning out.

[Terminal_Crazy]

Adjust the throttle stop and datalog the IAC position. You want it to be less than half the steps when the engine is at operating temp. If you leave the IAC steps too high at idle it won't have any room to control it.
That cam will not have much torque at idle to keep the car moving with the throttle closed. It may be the nature of the animal. The above adjustment may help.

Hi

I drilled out the IAC passage on the throttle body. Blades closed as far as they'll go. All as per the usual correct setup. TPS sensor checked voltage etc.
Engine in last log was idling with IAC around 28 steps.

Looking on a section of log, 5.5% throttle, motor starts kicking. IAC is faily stable moves from 38 down to 37 then to 36 with at least 3 logs between.
This TPS% is above the setting for the Individual Fuel trims so I have the suspicion I'm in the transition from trimmed to No trimmed Fueling.

I'll adjust & check this weekend.

Thanks
Mitch