Hello everyone,
Every time I turn on the A/C the idle speed increases from 500 to 1000 RPM and then goes back down to 500 RPM and this process repeats itself at traffic lights and stop signs as long as I have the air conditioning on. When this happens I've noticed that the vents will blow air that is warm. When the idle increase/decrease stops, the vents will blow cold air again. Could someone give me some ideas of what may cause this?
2002 Cavalier
When the AC cycles on, the engine is put to work, and needs the extra RPM to counter the drain of the compressor. There isn't alot of extra horsepower at idle.
My wife's GMC shudders on the expressway everytime the AC turns on or off. But it's done that since new. When it kicks on, it feels just like you tapped the brakes, then when it shuts off it's like bumping the gas. It gets very annoying.
Without knowing how old the ac system is, I'd say it might be time for a refresher service due to the low rpm warm air.
I'm just cuious what kind of car this is on, I can't get my cav down to 500RPM and keep it running.
when i turn my AC on my car just turns in to a vibrator
but thats all my polly bushings haha
check your a/c pressure you could be to high and it will trip the system. causing rpm jumping and warm and cold air
even with my ac on my cavy idles at 500 same as it would without the ac, also on our cars i wasn't aware the compressor cycled on and off i always thought it kicked on when you turned the ac on and stayed on continuously until you turned it off i've never noticed my compressor kick on and off. The fan may kick off once you get up to road speed maybe it constantly runs as long as the ac compressor is on no matter how fast your going. Mine too will blow warm air at idle i just had my system recharged didn't show signs of leaks or anything but wonder if the outside temperature would have anything to do with how hot or cold the air comes out of the vents, Because mine isn't very cool at all during the day yet once the sun has gone down and it's dark out it's almost ice cold but it's also been 114 115 here lately too.
the system (ac) is low on pressure take it to a shop and have it serviced with dye, thats the right way
Dye is for finding leaks.... it's not really a "service" thing...
Or he could just check the pressure and charge it back up himself if it's a little low...... for around $20....
Hell.... I replaced my compressor and fully recharged my A/C in my driveway.
I've seen products on some of the auto store shelves say something to the effect of dramatically reduces engine temperature makes your ac blow colder etc, are those products any good they even have some that reduce transmission temperatures as well.
I noticed these last couple of days the idle acts weird more when the ac is set at max. I would get ice cold air then suddenly the idle jerks up and down and warm air comes out of the vents and then 2 minutes later it's back to cold air.
2002 Cavalier
