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Davidf · 05-23-2022, 02:10 PM

It is my understanding that the ECM can react quicker to compensate for the added a/c load than the IAC valve alone. Also, if you have low vacuum, then I believe the IAC valve cannot compensate alone for the a/c load. Others may need to confirm this.

Best practice is to use at least the 12v a/c control input.

05-23-2022, 02:10 PM	#6
Davidf Registered User Join Date: Nov 2014 Location: Austin Posts: 749	Re: AC on idle issues It is my understanding that the ECM can react quicker to compensate for the added a/c load than the IAC valve alone. Also, if you have low vacuum, then I believe the IAC valve cannot compensate alone for the a/c load. Others may need to confirm this. Best practice is to use at least the 12v a/c control input.