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Discussion Starter · #1 ·
Well, I am going to drop off the car today afternoon for it could be work on tomarrow morning, I haven't turned on the a/c since last fall and now when I turn on the a/c the car seems to lose performance/power. The car acts weird with the a/c on, slow accelaration and weird low humming noise. When I talked to the service guy on the phone and he told me that the rpm suppose to go up when turning on the a/c, but mines goes down to under 600 rpm. I got the pcm udate last december, so I don't know if I need it again.
 
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Re: turning on the a/c

Mine does the same thing. I'm pretty sure it's normal.


Correct me if I'm wrong anyone. But when you turn on the a/c I believe the drive belt then needs to spin the "compressor" thus putting more strain on the engine and you lose some power.



I'm pretty sure I am correct. Please anyone correct me if I'm wrong.
 

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Re: turning on the a/c

+1. If you pay attention to any vehicle, you can hear the compressor kicking on and off by the engine idling down a little and a huming noise. That is how I found out that my compressor was bad in my 4Runner because I didn't here it kick in.
 

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Re: turning on the a/c

yep same here. But i can say one thing the AC does not seem as bad as other cars i have driven. I was driving with myself, my wife and the 3 kids in the car with the cruise set. we were going up and down so good sized hills and did not have to do anything the little 4 bannger kept right up.
 

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Re: turning on the a/c

You should lose a little power but the rpms are supposed to compensate when the ac kicks on. It should stay at the same rpm or higher automatically. If the rpms drop noticably then I would definitely think that something is wrong.
 

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Discussion Starter · #7 ·
Re: turning on the a/c

I will keep everyone posted, see what they say or do.
 

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Re: turning on the a/c

once you get things checked/repaired, try to use the a/c or defrost at least 10 minutes every 2 weeks all year long in winter and summer. Your a/c will work more reliably and last longer as the lubricant gets spread through the system regularly. I've done this for years on all of my vehicles and never had an a/c repair required on any of them.
 

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Re: turning on the a/c

Not a big fan of the ac system its either silent and not working or to loud and working to well. I prefer not to use it since its probably better for MPG and the engine. During winter I usually just use the heated seats and a jacket. I would run it occasionally though to avoid problems lack of use can be just as bad as over use, that goes for the car as a whole
 

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Discussion Starter · #10 ·
Re: turning on the a/c

They checked the car and they couldn't find anything wrong. They said that is normal because of the compressor. But for some reason the car runs alot better. They must of done something because the car feels more responsive with the A/C on. Can they do the pcm update without they telling me?
 
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I doubt they did that. They probably disconnected the battery for a little bit, thus resetting your cars pcm. Which means your car has to re-learn your driving style.
 
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