Revs Dont Go Down With Ac On!!!!!

[e30 gangsta]

So I drive my car and all is normal. When I turn the ac on and give it gas the revs like to stay up and come down very slowly. Ill rev to 5k and it will take like 10 seconds for it to come back to 1k. Anybody have any idea what this has to do with the ac? It only happens with the ac on thanks.

[EtaSport]

Doesnt make much sense. The ecu is supposed to bump up the idle with the AC on. Try unplugging the connector from the AC swtich to the ecu and see if it still does it. Its under the glove box near the ecu. I think they use purple wires with a black connector.

[e30 gangsta]

Doesnt make much sense. The ecu is supposed to bump up the idle with the AC on. Try unplugging the connector from the AC swtich to the ecu and see if it still does it. Its under the glove box near the ecu. I think they use purple wires with a black connector.

and if i dissconect it and it doesnt do it anymore what happens? What does dissconecting that plug do? Will it affect my ac or driving?

[EtaSport]

I never hooked mine up when I swapped harnesses, but I took out the AC. If you unplug it, your idle might be too low to run the AC. I was only suggesting because as far as I know thats the only link between the AC and the fuel injection.

All this connector does is put the idle around 850 rpm with AC on.

[e30 gangsta]

Dude you my friend are the man it worked! Anyone else know what the other connecter does? Thanks for the help guys.

[wagonizzle]

Old school bump! I have the same problem... any more info on how these are connected and what needs to be done to make it factory fixed (as opposed to just making the problem disappear)?

[87-325ic]

If you explained it like you did, it sounded like the time i left my TPS unplugged.