Which function increases idle with A/C on?
 

I have a 90 Formula with an LT1. I am trying to figure out which wire causes the idle to raise with the A/C on. A/C request is hooked up and I will scan it tomorrow to ensure it is working.

Re: Which function increases idle with A/C on?
 

I just replied to post about AC lugging engine, here is post about editing computer for higher idle and what not.

http://web.camaross.com/forums/showthread.php?t=464306

this is on 94 & 95 LT1's using TunerCAT EE definition.


If i remember right, A/C request need to be grounded to commad it. If the pressure switches for the AC are not in correct state, it may not command higher idle.

Re: Which function increases idle with A/C on?
 

I am going to wire in the LT1 pressure sensor and see if it helps. I am also going to wire in an A/C relay. I have it running seperate from the PCM right now and it is really pulling the engine down. Is the evap temp sensor neccessary or can I ignore it?

Re: Which function increases idle with A/C on?
 

what year lt1 are you working with?

Re: Which function increases idle with A/C on?
 

94 hotcammed LT1 with a T56. I was wondering if the cam could have something to do with it. The A/C has caused me more grief than the engine swap. I reran my A/C request wire today and it doesn't die anymore. What does the A/C clutch status do?

Re: Which function increases idle with A/C on?
 

On my 94 there are three wires going to the ac low pressure switch. One of them is under voltage when ever the ac switch is on. Jumping the hot wire to one of the wires kicks in the ac clutch. Jumping to the other one raises the idle. That tells me that a faulty low pressure switch could cause this problem. I hope that makes since.

Re: Which function increases idle with A/C on?
 

I don't have that sensor. I only have the thirdgen cycling switch. I am going to borrow a scantool tomorrow to make sure the A/C request is working.

Re: Which function increases idle with A/C on?
 

A/C request is working. My car sometimes idles up properly and other times it still wants to die. Would wiring the pressure sensor help this? What about the A/C status wire?