1999mustang2000

Idle up and down with the a/c or heater or even the defroster on? because mine does and i'm not sure why..ill hear a click and then itll idle up and then back down

Sxynerd

Yes, it's supposed to. but how high is yours going? It shouldn't go past a 950-1k. The click is the compressor clutch activating. If your "click" is loud check to make sure you have the 3 bushings still in place on the C. clutch.

1999mustang2000

um mine idles around 800 in D and when it clicks on it raises to around 1100

Sxynerd

Yeah, it's too high. 800 good. did anything new in the last few days? Unplug the battery then reconnect and drive it around for a while. If it doesn't help, then check your TPS.

1999mustang2000

brand new tps but its always done it my dad just brought it to my attention the other night.....itll click on rev up then back down and about 10secs later itll do it again and itll keep doin it as long as the climate controls are on

Sxynerd

It's supposed to turn on when you have the selector switch on A/C or Def or the foot/def setting. The idle is too high though. How old is your IAC?

1999mustang2000

is it supposed to come on repeatedly? and im guessing as old as the car is which is an 03 ive had the car a year and ive never replaced it

0949er

my car shuts off sometimes when I first turn the a/c on

but I blame it on the cams..... haha


yes the compressor will click on and off. It only has to cool the coil down, and once it does that it turns off. once it heats back up it comes back on (helps you save energy)

your just putting a electrical "load" on the engine and it takes it off guard for a second until it can kinda "self-correct"

you are saying that it "idles" at 1100 w/ the a/c on and 800 with the a/c off?

masterofthepuppets99

well this may be totally separate but... the defroster runs off the a/c compressor and my a/c system was not charged fully (a leak or something) so when i would turn on the a/c my idle would go way up and then fluctuate. after i addded more r-134a to my system my idle returned to normal. normal as in 600 rpm idle and 850ish rpm idle with a/c on. just my opinion. good luck and ( to 1999mustang2000) i just got the wheels today, they look good but im gonna check em out some more tomorrow when i have more time

1999mustang2000

ok thanks and i hope you like them i really did and i almost regret getting rid of them