[ThangCu35]

I have a problem with my idle with A/C on. My setup is 2zz PFC. It works fine in the past, but just for the past few weeks the A/C idle up has been erratic and now my idle is 2200-2500 RPM whenever A/C is on. Is there any easy way to disable the A/C idle up? Since my idle normally is at 1100, I don't need the idle to be any higher than that.

 

[rcntype]

Just go to the settings tab and adjust the AC on idle to match your normal idle. Should be Settings 1

 

[ThangCu35]

Wish it was that simple..The problem is it doesn't matter what idle speed I set for A/C in PFC, it will still shoot up to 2500. It's bypassing the throttle valve and letting air into the engine.

 

[rcntype]

Oh you didn't mention something is wrong with your car. Then its not a pfc issue its a normal eratic idle issue :lol: Maybe your iacv is bad?

 

[ThangCu35]

Oh you didn't mention something is wrong with your car. Then its not a pfc issue its a normal eratic idle issue :lol: Maybe your iacv is bad?

I'm thinking that also. Idle without A/C on is still good, it sits where I set it to. That's why I'm looking for a way to disable A/C idle up.

 

[Cap Weir]

Idle without A/C on is still good, it sits where I set it to.

It's not the IAC.. it's a setting in the PFC..

Cap

 

[ThangCu35]

Cap, I set my A/C idle in PFC to 1200, but the car doesn't listen. How can I disable A/C idle up?

 

[Cap Weir]

I do not speek PFC, but it the Car EVER idles like it should, then you ask the AC to come on, then it's the PFC that will step up the Idle Speed for the AC..

Now is it posable the AC is not coming on, and the PFC has raised the RPM too High?..

Cap

 

[rcntype]

I do not speek PFC, but it the Car EVER idles like it should, then you ask the AC to come on, then it's the PFC that will step up the Idle Speed for the AC..

Now is it posable the AC is not coming on, and the PFC has raised the RPM too High?..

Cap

Even if the compressor doesnt turn on or if you don't even have a compressor connected if the AC button is pressed or defogger turned on the PFC will tell the engine to idle up. I know this because my car does not have a compressor.

 

[Kevin Beane]

First make sure the upper limit is higher than the lower limit for each condition (like A/C on). I recommend at least 200 RPM difference, otherwise it may "hunt".

If the IAC is bad, it is probably bad when A/C is off.

Try making the A/C on idle settings the same as the A/C off idle settings. Does it idle OK? If so, there is probably something wrong with the data in the cell(s) that are being used when the idle goes up. This means you need to adjust timing or fuel there.

However, there's a known problem with changing idle settings in the PFC... sometimes. After you change idle settings in the PFC, they don't always "take".

Make changes to idle settings, then save your settings to a file using FC Edit. Important to make sure you've saved it, so do a READ ALL, SAVE AS and remember the filename. Load that file to verify. Then, with the engine not running, but ignition key on, do Reinitialize Power FC. That loads default data from the ROM into NVRAM (working memory) inside the PFC. Turn the ignition off. Wait a bit. Turn it back on. Then do a READ ALL to make sure FC Edit is still talking to the PFC. Finally, open your saved file and write all.

 

[Kevin Beane]

A/C idle up: I'm pretty sure that's a discrete input to the PFC (meaning one wire going in). I'm not going to suggest cutting a wire.

 

[ThangCu35]

I'm going to do as you suggested. Probably due for a idle relearn anyway. If this doesn't work, I'll be hunting for that a/c wire.

 

[AChan]

I have a similar problem but my car is stock.

When I first turn on the AC, there is a loud grinding noise for a second. I thought I ran over a branch with leaves on it the first time it happened. The idle jumps to 2k then drops to 300 rpm when the AC compressor kicks on. Sometimes, it feels like it's going to die.

I drove it in the rain last week and every couple seconds, the rpm would drop and there would be a slipping noise like the belt is slipping on the pulley...Has this ever happened to anyone?

 

[AChan]

No comments about my previous post? I'd like to know what's happening...

 

[ThangCu35]

If the belt is slipping when A/C is turned on, your A/C compressor is possibly at fault. It's creating more than usual friction and that will drag the engine down to a stall.

 

[AChan]

Hmm...The previous owner said he had the AC compressor replaced recently. He gave me the receipt too...This sucks...

 

[OldMan]

Post Deleted

 

[AChan]

That's an interesting point. I'll have to figure that one out...The previous owner said he had a shop replace the compressor. I have the receipt for it. I'm guessing the shop screwed him.

I turned the AC on when I first got the car, it never got cold. So I bought some R134 from AutoZone. After filling it up, it started clicking and bogging...Did I break something? Sounds like too much refrigerant pressure.