Ok, I posted something similar to this before, but I think its a completely different issue now. I recently noticed that my A/C compressor has been turning itself on and off regularly. It'll be off for about 15-20 seconds, then it'll turn itself on for about 10-15 seconds. No A/C blows out my vents, its just the compressor kicking on. Now I'm not sure if this is normal or not, for I never noticed it before, but then again I never really payed any attention to it. So it that OK? I KNOW this is hurting my performance, cuz I can feel the lag when it kicks on, so right there it's pissing me off, but I know it's hurting potential fuel economy as well. If this IS abnormal, anyone know how to fix it? Is there maybe a way to override the compressor temporarily when I'm at the dragstrip to make sure that doesn't happen? ANY help is greatly appreciated. Thanks guys!

Bruce (90RS305)

 

My car does this too. As near as I can tell, the cause is that it is low on freon in the a/c system. This is probably bad. If the situation is not taken care of, the compressor could be damaged, and you could even lock up. This could take out the belt, which would possibly leave you stranded.

You should be able to disconnect the compressor electrical connector and it will stop. Also don't use the a/c or defroster settings and it should never try to engage the compressor in the first place.

Since mine is a "toy" car, I don't drive it much and I don't plan to fix it. In fact, I plan to remove the a/c completely.

 

Hmm...it better not be low on freon, I JUST HAD THE WHOLE SYSTEM REPLACED when I got it! That would SUCK! And I actually rarely use my A/C, I just assume cruise around with the windows open, but it still does it!

Bruce (90RS305)

 

Sounds like a bad wiring connection to me. Your compressor shouldnt be engaging at all until you turn your a/c on. Then if it IS low on freon it will cycle RAPIDLY..like 1-2 seconds between engaged and disengaged. 10-15 second cycling is normal for operating a/c. So for some reason your compressor is operating when your switch is off....so find out why. Take it back, tell em about it

 

You should be able to get a quick reading on this by using the vent or heat setting on heat controls, or turn it to off. If this "fixes" the problem, then it is quite likely freon.

I feel your pain on the fixing of the a/c. That is why I'm not fixing mine. Way too expensive for how much I drive the car. I'm also looking at some other mods and I'm wanting to clean as much unneeded stuff out from under the hood as I can.

Also as a note, even when the a/c is working perfectly it takes power when it is on. I would always make sure you use a setting that leaves the compressor off when trying for that all out performance.

 

I know the A/C takes power from the car when it's on, that why I want it off! So from what I'm gathering if I have my system set to "HEAT" then my compressor should not turn on at all? (FYI = heater does not work either, which needs to be fixed before winter, too) And if that happens, then it IS freon? Unfortunatly I couldn't take it back for a free fix, I got it replaced in July of 02'.

On that note, could I potentialy remove the wireing connection (pictured below) from the A/C compressor without it throwing up the SES light? And would it effect my computer adversly? If not I could use that as a temporary fix at the dragstrip...

Bruce (90RS305)

 

You could also remove the electrical connector on the back of the accumulator (clutch cycling switch)..

 

It shouldn't be coming on with the selector set to "heat" or "vent", or "off" (duh).

It should come on in all other positions, including "defrost".

It cycles because it's low of Freon.

I highly recommend keeping the A/C on and working. The amount of power that it uses when not turned on is negligible; and working A/C is worth a considerable difference to the resale value. Not to mention your own comfort, if you ever drive to, or move to, a plcae where it's hotter. Plus, it would be kind of dumb to spend all that money on replacing the whole thing as you describe, and then let it decay again.

The system as used in these cars leaks slightly, always. It's unfortunate but true. Even the rubber the hoses are made out of, is permeable by the Freon molecules; so a few molecules will be constantly escaping. The newer "barrier" type hose with a polyethylene liner doesn't leak anywhere near as much, but your OE hose isn't that type. They usually leak about one can every 12 to 24 months. You can probably get it back happy again just by replenishing it.

 

Thanks, that about summed up what I was looking for. I did have the ENTIRE system, tank/hoses/compressor and all, replaced the week I bought the car. So roughly the week of July 7th, 2002. I did a lil' experiment last night and the compressor STILL kicked on while it was in the "HEAT" position. What does that mean? Also I had another problem that I didn't think was an issue, but maybe I was wrong...Sometimes when I have the A/C on (or anything other than OFF for that matter) when I turn it off it doesn't turn off, it just re-directs the air towards my feet. I have to keep sliding the selector back and forth a few times before it'll go. Could that have anything to do with it?

*EDIT* How hard would it be to pull the selector unit out of a junker and replace the one in my car, if maybe thats the problem...?

Bruce (90RS305)

 

That does sound like your control panel is fornicated.

THey're pretty easy to change out: there's about 2 or 3 electric connectors, the one big vacuum "plug" with about 5 or 6 vacuum lines going to it, and the heat door cable which just unclips.

 

Groovy. I'll do that before I go and spend $19357031 on a pound of R-12. If not, ohh well...

 

The less freon you have the faster it will cycle on and off. If you have a slow leak, it will probably start cycling off about every 30-45 seconds. It's hard to notice at first. If mine was cycling every 10-15 seconds, I'd fix it before it wore out the clutch and compressor relay.

 

THAT long? Hmm.....news to me. Both my Camaro and my Mustang had roughly 15-25 second cycling... Course I dont have the Camaro now and the Mustang, I KNOW it has a slow freon leak. But it only leaks when I use it, which isnt often. So why fix something that I use once a month or less anyways.