A/C Problem (Compressor?)

james22 · 01-02-2011, 07:07 PM

Hi All.

I have only just started using the A/C in the car over the last week.

Anyway, I noticed a few days ago that the compresser seems to be cutting in and out constantly. ie. click on - 1 sec later - click off.

The A/C still seems to work fine, other than the compresser cutting in and out constantly.

I have noticed that at idle, the A/C doesnt appear to work as well as usual, but once driving (above 2000 odd rpm) it seems fine.

Anybody have any ideas?

I've checked the connection and it appears secure, but I have no bloody idea what else could be the problem.

Cheers in advance

galaxy xr8 · 01-02-2011, 07:26 PM

Not low on gas ? .

james22 · 01-02-2011, 07:32 PM

I have no idea, I've never re-gassed it in the 5 years i've owned it. So that is definately plausible.
Does the compressor cut in and out when low on gas?

vermiltina · 01-02-2011, 08:22 PM

yeah they have a pressure switch in the system so if theres no gas/pressure in the lines it won't opperate to stop from stuffing the compressor completely
go get the system checked. it might have had dye put in it so if leaking is easy to find.

galaxy xr8 · 01-02-2011, 08:56 PM

Yeah mine did when it was low on gas, that's all it was.

james22 · 01-02-2011, 09:16 PM

Cheers fellas, my first port of call is to check the a/c at the local shop I suppose.

I'll check back with results later.

Thanks

galaxy xr8 · 01-02-2011, 09:24 PM

No worries mate, it's normally this time of yr when you find problem's with the air cond as it's when it is needed, 40 deg today

DW260 · 01-02-2011, 10:13 PM

Yep, same thing happened to me this time last year. Turned out the compressor was shagged... Similar symptoms to mine, but mine wasn't getting cold at all.

GASXD · 02-02-2011, 08:21 AM

Hi James,

When you switch on your A/C do the fans come on regardless of engine temp?
If you have a condennsor thats getting to hot it will casue the commpressor to cut in and out to combat the heat buildup (safty messure).
Now you mention it works fine while driving at say 2000rpm around 100kmh or so.
This would provide enough airflow to cool the condensor and keep it happy.
My guess is that if it was low on gas it would cut out regardless of rpm or vehicle speed. I would be looking at the electrics that switch on the fans also.
Worth a shot before you blow all your cash on a regass.
Aslo, not sure if it works on AUs but on the E series if you unpluged the temp sender harness from the sender it used to make the fans come on flat stick, might be worth a try as that would cool the condensor and stop it from cutting out.

Cheers

Doug

james22 · 02-02-2011, 09:44 AM

Hi GasXD

The thermofans only switch onto high speed at around 92.0C.

They go back to low speed once it drops back into the mid 80's

Thermofans have always worked that way since I've had the vehicle, and I've never had a/c problems before now.

When i mention 2000rpm, its not on a hwy.
I can be sitting still, and at idle with the compresser cutting in and out the air is only sort of cold, but with a few more rpm (2000+) and still not moving the air will go cold. I think its just the extra rpm's making that compresser work more for the second its on before it clicks off again.

Another reason I don't believe its the condensor is that I can start the car (stone cold) first thing in the morning and straight away the a/c is clicking on and off, and nothings even warm at that point. So that should rule out the condensor?

Thanks for the input though, all idea's welcome lol

AMB · 02-02-2011, 06:38 PM

Could be electrical, maybe the pulley clutch. Unplug the clutch wire (the single wire near the pulley), and connect it to 12 volts directly. This bypasses the pressure switch and everything, if it still clicks off and on, then it is a faulty clutch. Don't let it run like that for very long (in case it is low on gas).