MSefi.com read only forum (Jan.15,2018)

Hi,

there is a minor issue with the idle speed. There are conditions when it settles to 850/min of 1100/min. I think I can trace that to the temp-related table for stepper moves which I seem to have mixed up. The min.amount of steps to let it move was set to "5" and I asked it to do 3 steps between the points of the table when the coolant was almost hot.

Question is if I have to correct the 10-point table OR if I can reduce the amount of min. steps instead.
What is the usual min. amount of steps that one would want it to do ? The stepper I have is the same as the screw-in-GM-type from the manual.

The most accurate adjustment is setting min step to 1. If this gives a consistent idle when the engine is thoroughly warm then that is the best. If idle is not consistent, then look at the idle step position in MT/ TS when engine completely warm - is it consistent ? If not, then there is some sort of configuration problem. For example there is an extended fast idle setting or you are not reaching the last temperature in the temperature table. If it does reach the same idle step position each time and the idle is different, and there are no vacuum leaks, PW and timing are the same each time, etc., then that is when you may need to choose a higher min step, because the motor sometimes doesn't move when a step is changed.