Strange A/C problem

[Noiseypackerfan]

OK My A/C belows cold air, Then the ac stops working, The clutch disengages. Now here is the strange part, When you kick the throttle down for just a few seconds the clutch kicks on, Several times now when the clutch kicks off I will stop the car leave it running in park grab the throttle rev it up let go quickly and boom the clutch kick back on, So I know it is not the blend air door any Ideas ?

 

[Noiseypackerfan]

Wow this must be more serious than I thougft

 

[TheMasterPing]

Well....since the smart experienced people havent chimed in, i'll go ahead and throw out there a few obvious tips.

Have you checked or had the charge on the system checked? It's got safeties that keep it from running if the charge is too low, maybe it's hovering around that limit.

Others have mentioned elsewhere checking the switch on the condenser that IS the safety mechanism, which apparently can go bad.

Could ofcourse be the clutch going bad, but i dont know if what you have is a symptom of that.

-Ping

 

[paart]

Your AC system is designed to cycle (the compressor off and on). It sounds as if yours may be cycling excessivly. The most frequent reason for this is low refrigerant level. If you want to verify this, remove the large electrical plug from the accumulator, jumper the two plug connections with a short piece of wire, start the engine and turn on the air conditioning. The compressor should run continually. Do not run it too long, like this, (10 min or so at the most) as the evaporator could freeze up. Or, go to a shop and have the freon level checked.

 

[wallerus]

There is a pressure cycling switch (low pressure switch) and a high pressure switch. Two things (of many) could be happening. Low refrigerant level or high pressure.

If the electric fan is not working (depending on if equipped) the pressure in the system can get above the limit of the high pressure switch causing it to shut off the compressor until the flow thru the condenser is enough to lower the pressure in the system.

Does the problem only happen at low speeds or idle?
It can be checked by placing a good sized fan in front of the condenser and seeing if it still shuts off.

The pressure in the low side system is regulated from 23-25 psi to 45-49 psi.

Try the fan trick first. If it works
A. Check to ensure electric fan is working (if equipped)
B. Check for obstructions of the condenser (bugs, leaves and stuff).
C. Most important, Put a set of gauges on it and check for proper charge.
D. Make sure the fan shroud is in place for the mechanical fan (if equipped)

If the system has been changed over to R134 without the hose and compressor change then the system will bleed off refrigerant naturally and need to be recharged occasionally. If you recharge it, ensure that your pressures are correct as 134 only uses about 80% of and r12 charge.

 

[Noiseypackerfan]

OK The charge is good, One of the two fans comes on and stays on, even when the clutch kicks out, It has no pattern when it kicks off, can be at road speed, town speed, or parked, When it kicks off it will not kick back on until you rev engine up, It was 95 yesterday and driving home from work it cooled the car down very well, It just strange,

 

[paart]

How did you determine that the charge is ok? It seems to be normal for one fan to operate continually while the air conditioner is running, compressor clutch on or off, at least in warm weather. If the car is cooled ok, I wouldn't worry about it.

 

[Noiseypackerfan]

I used a ac Gage,between 30-45 psi I thought fan operation was ok just wasnt sure,

 

[selection7]

I have this exact problem. Mine is a 95 Lesabre, and whether the a/c clutch turns or not is almost totally random. I can hear a 'chick' sound when the clutch engages and disengages, and sure enough, when it does engage (I can see it turning/not turning), cold air blows. Sometimes it doesn't run even right from when I first get in the car, so it's not likely a high pressure issue (**see note at end). I've had this problem for a full year now and the a/c sometimes stays on for quite awhile and cools very well to this day, so it seems unlikely it's a low pressure leak problem or the thing would probably not be working period (or rarely) all this time later. If it was just the result of a natural, expected loss of refrigerant pressure, wouldn't these symptoms be happening to everyone who's refrigerant gets low?, and yet from these forums and people I've talked to, these particular symptoms are rare.

Also, sometimes the clutch engage goes either off or on regardless of car speed, rpms, or how long the car has been on. However, when it's not working, revving up the engine will always make the clutch engage again, though it takes more revving if I've recently pulled that trick a couple of times. Weird. Sometimes it sticks and I get cold air for many minutes, sometimes the cold fades away almost immediately after I let off on the accelerator. This relationship with throttling up the engine seems to suggest it's not an electrical problem.

Noiseypackerfan, let me know how you solved it if you did.

**NOTE: I found this about a Volvo with a similar issue:
http://vol940.blogspot.com/2010/06/ac-working-now-finally.html
But I'm not completely sure, is he saying the problem was the pressure was too high? Remember, sometimes my compressor clutch won't engage from the very first moment I get into my car and turn it on...so how could the fan on the compressor be the issue, as wallerus mentioned? I guess it could be high for another reason.

 

[selection7]

As an update, a guage to the low side port reads that pressure is on the low side. I read that if there is a blockage, pressure would be low on the low port and high on the high port, so there's that...or there's possibly not having enough refrigerant of course (which I still can't resolve with why the condition hasn't changed in a year if there's a leak)...or possibly I was hasty before when I suggested it's not an electrical problem because accelerating makes the compressor clutch engage. I say that because there's also the possibility that the low side switch/sensor is only mis-reading, rather than outright not functionioning, which I hadn't previously considered.

 

[PatDTN]

3 out of 3 of my RMWs were doing that and were fixed by adding freon (okay, R134A) using those cheap can and guage sets from the auto parts stores. Oddly the pressure went up a bit then down before the clutch locked in and stayed in. Had the temp set for 60 to keep it running. Now 3 of 3 cars throw snowballs at me when I turn it on.

 

[epstacey1]

try re-setting cc system- disconnect battery i believe , mine acted wacky until reset, now works great

 

[Noiseypackerfan]

Ok what I found was the cap on the high side was leaking, New cap new valve, recharge no more problems, Thank to every one for the input !!!

 

[selection7]

try re-setting cc system- disconnect battery i believe , mine acted wacky until reset, now works great

What's a CC system? Google didn't clarify.

 

[Krzdimond]

CC= Climate Controll

 

[selection7]

Thanks Krzdimond. Would my '95 LeSabre even have a quote-unquote Climate Control system? It doesn't appear to monitor either the outside or inside temperature and all the AC controls are fairly barebones and manual.

 

[Ozzy]

If it doesn't have a digital display then no it isn't.

 

[Rebmob_7577]

3 out of 3 of my RMWs were doing that and were fixed by adding freon (okay, R134A) using those cheap can and guage sets from the auto parts stores. Oddly the pressure went up a bit then down before the clutch locked in and stayed in. Had the temp set for 60 to keep it running. Now 3 of 3 cars throw snowballs at me when I turn it on.

Hey! I’m having an issue with this on my 96 RMW, and the little gauge I bought from autozone to recharge it at home says it’s reading like 35psi on the port up top when set to manually to 60 with the fan all the way up. Where’s the low side port, and should I just ignore that gauge I got completely? Because I’ve had this going on for just over a year now and it’s always read within the parameters since I bought the kit

 

[Scrapmetal1009]

Well....since the smart experienced people havent chimed in, i'll go ahead and throw out there a few obvious tips.

Have you checked or had the charge on the system checked? It's got safeties that keep it from running if the charge is too low, maybe it's hovering around that limit.

Others have mentioned elsewhere checking the switch on the condenser that IS the safety mechanism, which apparently can go bad.

Could ofcourse be the clutch going bad, but i dont know if what you have is a symptom of that.

-Ping

had a jeep grand cherokee that did the same thing I took the clutch apart and removed a washer which closed the gap a bit worked fine after

 

[G-833565]

My car is 2011 buick regal the compressor clutch engage all the time but the ac cooling too slow. I have driving around 5-10mins to getting cold. Any one have experience with this. Please, help