Hey there, I have a 1992 Camaro Z28 with a 305 TPI. In the process of trying to get it to pass emissions.

Yesterday we switched back to the stock thermostat so that the engine will run a little hotter and burn more hydro carbons so I can pass the test.

During the swap we moved the throttle body out of the way so that we could access the bolts on the thermostat.

Put in the thermostat, re-connected all of the electronics. After connecting everything she started and idled fine. I let her heat up until the coolant was running, there was a bit of a leak on the main rad hose so I turned it off and tightened the hose again.

Started her up again and now she doesn't idle. If I hold down the accelerator she will run but if I let it go she completely dies.

Before I run off and spend more money on this thing, I'm looking for opinions.

 

I think all will agree, first check the obvious. No damage wires or leads to the TPS and the IAC. Your also going to want to make sure the gasket under the TB is not leaking. The next thing would be to reset the IAC to factory. I understand that the car was running fine when you first started it. Therefore I would think that it is not somthing new. The IAC needs time to idle-in once you have diconnected it adjusted and reinstalled it. When I replaced mine I could hear the engine hunting and the air flow increasing and decreasing as the IAC came into sink with the ECM. Thats really the only thing that comes to mind. I hope it helps.

 

I probably should have replaced the gasket on the throttle body when I removed it. Pulled off the IAC and it seemed fine. Checked throttle body, but no luck.