Hey, find someone that can read the ECM info. I have a quickcheck 2, got it pretty cheap, and can read what the computer reads to tell if that sucker will kick in or not. Two things have impact on the cold high idle.
1 By the time the heater grids stop, there is substantial heat from the engine getting to the IAT, thus requiring colder temps to get the IAT down to 32.
2 That chunk of iron takes a long time to cool off, this will affect the IAt also, unless it sits for a long time.
Once you get it working and understand it, you will love it, for example,
Iowa, -12 deg F. , Start, idle up, 3 cylinders, almost no delay, then the good part.
EGT reads almost 600 deg F. !!!!
Just make sure the fuel is treated, this is the weak link.
Nick