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Continues to rev

2K views 15 replies 6 participants last post by  Codysmustang 
#1 ·
Ok so I just got my 02 gt last week and see I got a long way ahead of me.. A very long list of issues that need to be fixed.. But when I sit at idle with ac on my car revs up and down all the time.. I never had a car do that before.. Is it so posed to?
 
#2 ·
The idle will fluctuate, a little. Depending on when the a/c compressor is cycling off/on. Its a huge drain on the car, electrically and the engine.

Now, if its cycling a lot, meaning your rpm's are moving up and down frequently, its probably because you're low on freon (r-134a). Is the a/c blowing as cold as you would expect, or no?
 
#4 ·
Codysmustang said:
No.. It hardly blowing any cold
Then I answered your questions. : )

Take it to a shop, have them do "a/c service". Meaning, charge it full and put a/c dye in it. Then drive the car. You may have a VERY small leak, and the charge could last for years. Could be opposite though, you may be leaking so rapidly that you'll run out of freon in a few days.

If a shop tries to do it any other way, ie, telling you to replace a condenser, or line, etc, dont listen to them. Theyre more than likely trying to rip you off. Charge it, put dye in it and drive it. And go from there.

Good luck!
 
#5 ·
could be something like the MAF sensor or IAC (idle bypass valve) not working right or needing cleaning. Air filter as well. Thats where to start then you can get into more troublesome items. You can also scan the car for any codes.. might have some but not showing a CEL code.
 
#6 ·
SpectorV said:
could be something like the MAF sensor or IAC (idle bypass valve) not working right or needing cleaning. Air filter as well. Thats where to start then you can get into more troublesome items. You can also scan the car for any codes.. might have some but not showing a CEL code.
If it was a MAF or IAC issue, it would throw a code. For certain.

Since the "issue" is only happening with the a/c turned on, I'd certainly start with that.
 
#11 ·
my RPMs fluctuate with my A/C as well. i believe that is normal when the compressor kicks on and off. but as mentioned, i would def. have the A/C services if it is jumping rapidly.
 
#14 ·
Ok got the revving problem fixed.. It needed freon for sure then me and a frnd fixed the idle screw set a small amount higher and can def feel the difference.. It blows real cold, doesn't idle up and down, and sounds better.. Not got to bypass the O2, sensors fix abs problem, put 6 injectors in, put the new control arms on, and should be looking good
 
#15 ·
Codysmustang said:
Ok got the revving problem fixed.. It needed freon for sure then me and a frnd fixed the idle screw set a small amount higher and can def feel the difference.. It blows real cold, doesn't idle up and down, and sounds better.. Not got to bypass the O2, sensors fix abs problem, put 6 injectors in, put the new control arms on, and should be looking good
Glad to hear it!

Im guessing "bypass the o2" means rear sims...? Off road pipe?
 
#16 ·
Well because the car has been lowered and there no stock jack to be found I have to improvise to get under the car.. But it looks like 3" pipe from front to back.. I can't tell if the person that changed the exhaust even put new O2 sensors on it or not.. But most ppl I no just bypass them to get the code to erase.. Those sensors are a pain to maintain.. Especially if lowered
 
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