Hoping you all can help me out. I have pretty much an entire drivetrain out of an '88 GTA in my Elky and everything works as it should except for the fast idle. It idles the same when you first start it in the morning as it does when you park it after coming home from work. This causes the engine to stall when you turn on the A/C also. I have reset the IAC and set the RPMs for 500 in drive, and then I also reset the TPS for .48 idle to 4.5 wot. I checked the wire at the ECM to make sure the A/C was calling for high idle and it does in fact show 12 volts at the wire with it on. It has a Hypertech thermomaster chip in it, pretty much all stock other than a cone K&N and MSD coil, only one SES code which is for low activity O2 sensor. Any help is greatly appreciated!

 

If there is a signal at the A/C Request input to the ECM, the ECM should respond and bump the idle by 50-75 RPM.

I think you may have identified the problem. HyperScrap's programming is not renowned as being very sophisticated. I'll bet uyou either have no A/C adder or generally poor IAC control. That might also explain the lack of slightly higher RPM at cold startup.

 

Thanks for the reply. I'll try the stock chip and see how it works out. Is there anybody that you can suggest as far as burning chips?