Application: TPI converted Suburban with a stock TBI 5.7L engine using a #727 ECM.

For the most part it runs very well, but recently it will stall at idle. This happens occasionly and appears worse when MAT exceeds 120*F. I am not 100% positive, but am reasonably sure it has something to do with when the AC kicks on.

I did a search and came up with one hit: https://www.thirdgen.org/techbb2/sho...ght=idle+a%2Fc
I plan on checking the suggestions contained in the referenced thread.

However, currently, the ECM does not have the AC input signal. I would like to add that but do not know where to tap the signal. Should it be prior to or after the pressure cycling switch? And at what pin going to the ECM? http://www.chevythunder.com/fuel%20i...cm%20#1227727)

Any help would be appreciated. Thanks, Ed

TPI Conversion - 1994 Suburban

 

Sounds like it wouldn't hurt to try it.
I do know that you want the signal so that it is only present when the clutch is engaged. That is the one wire I forgot about during my rewiring and ended up connecting under the dash on the "switched" signal, not the clutch itself. I get the boost in rpm as needed but it is immediate and continuous. Would be better if it cycled with the clutch. I run my A/C on max anyway so the cluch is mostly on and it doesn't bother me. I'll probably fix that next winter.
Sorry can't help on the pin.

Edit : (C17 looks like it)