It was pretty hot this afternoon so i decide to turn the a/c on, figure check it out now before the summer comes. During idle(in park, at stop light) the engine will rev up and go back to normal about every 5 seconds( I dont have a tach so i dont know how much). I turned off the a/c and turned the heat on and did just about the same thing, just a little less. What should I look out for?

Thanks

 

I think its somewhat normal but I could be wrong. Whenever you turn the AC on the crank has to turn harder to turn the AC compressor. My car does this and revs between 500 rpm to 1k. Nothing messed up do far.

 

just asking, cause I dont remember it doing this last summer

 

Check the IAC Idle Air contorl, this device gets used a lot when the A/C is running at idle. Some times it gets weak and starts to fail or get slugish, mine got so bad that when I took it out to look at it, it fell apart in my hands. Get a new one if yours has been in there a long time or if it looks bad. The next then that will happen is your car will die at stop signs because it can't get any air at idle.

 

Mine does that very similiar problem. If I don't have my foot on the brake enough it could sometimes even lerch forward if I'm not payin attention.

Could you please help me to where I can find the IAC? I believe this is something I might need to replace.

Mark

 

I know how you feel wwasem, same thing is happening to me, Where is that IAC idle air control anyway guys??

thanks

 

The IAC is mounted next to the butterfly by two screws. If you standing looking at the front of the engine it will be to the left on top. looks like a motor, will have 4 wires coming out of it with a retangale connector.

 

The a/c settings and the defroster setting will cycle the A/C compressor on every few seconds to keep the compressor from freezing up.

If you put your car in neutral, and put the a/c on, and pop the hood, watch the a/c compressor. You'll see the clutch engage the a/c pulley, then disengage the pulley, then wait a bit, then engage the pulley, then disengage the pulley, then ....

 

So what you're telling me is basically this is normal and that there's nothing I can do to control this?

Mark

 

Just hold the brake on and check your IAC.

 

what should the IAC do? I'm new to this... should I see it move or something? I know at one point when I first installed my SLP CAI that I removed the IAC and the car got cranky with that and idled worth nothing, but I put it back in and that solved that. Thanks for your help.

Mark