A/C clutch going?

[Ian Macoomb]

On my Gen III the A/C compressor clutch cycles on and off every couple of seconds. It makes a loud clicking noise when the climate control is on anything but vent or off. It's done this since I bought the car nearly two years ago.

Is the compressor on it's way out or is it something simpler like low refrigerant?

Also, every time it clicks on the revs will climb a bit to compensate for the added load.

 

[projectSHO89]

Fast cyling is a sure sign of low refrigerant (normally).

Steve

 

[Slo-Sho]

I would check the refrigerant level, very easy to do. Your car requires R-134A Type Freon, costs about $4-6 depending on where you go. All the other symptoms that you've described are all pertinent to the operation of the A/C system. When the clutch engages, the EEC-V will increase the idle speed to compensate. As far as the "clicking" noise, this may simply be the clutch engaging or the relay switching (If heard inside the car). You will also notice that in both the "vent" and "floor" modes the A/C will be overiden. All of the above are normal.

 

[Ian Macoomb]

Wow, quick replies. Thanks for the answers. Next time I'm down in the states I'll pick up some refrigerant and top it up. Can't do it here since you have to have a license to buy any.

 

[projectSHO89]

Can't do it here since you have to have a license to buy any

Interesting...

Here you need the 609 certification to buy the older types such as R-12, but any fool can go to any Wal-Mart or AutoZone, etc and purchase R-134. It's also interesting that hydrocarbon-based refrigerants that contain propane, butane, or similar compounds are permitted in Canada for vehicles, but are not in the US.

Wal-Mart is the cheapest you'll likely find for the 12 oz cans of R-134. If you think you'll need a big supply, Sam's Club sells the 30# cylinders for around $70 USD.

Steve

 

[Ian Macoomb]

projectSHO89:

Can't do it here since you have to have a license to buy any

Interesting...

Here you need the 609 certification to buy the older types such as R-12, but any fool can go to any Wal-Mart or AutoZone, etc and purchase R-134. It's also interesting that hydrocarbon-based refrigerants that contain propane, butane, or similar compounds are permitted in Canada for vehicles, but are not in the US.

Wal-Mart is the cheapest you'll likely find for the 12 oz cans of R-134. If you think you'll need a big supply, Sam's Club sells the 30# cylinders for around $70 USD.

Steve

When I was at the convention I saw it on the shelves at Walmart. That kinda suprised me. Here the licensed technician is supposed to check the system for leaks before adding freon.

I'm not far from the border so I'll make a trip down sometime.

 

[rangerj]

Ian,

Keep in mind, that if you are low on refrigerant you have a leak. Look for any black oily or greasey spots near A/C connections. The oil circulates with the refrigerant. If you have leaked refrigerant, you have also leaked some oil!

Frequently the leaks are relatively small, and you can add a charge to the system that will last through the warm season. When you do get down here, you should consider getting a can of R-134a that also contains a small amount of oil.

There are even cans that have a few ounces of oil, a leak detecting dye, and a leak sealer, as well as the R-134a . This would be your best bet.
I have seen these at Auto Zone as well as Wall Mart.

The hose connection and the valve that you connect to the can are also sold at these places. Just be sure to connect to the low pressure side.

Your clicking sound, when the A/C engages, is the two surfaces of the clutch hitting when the coil is activated. The gap between the surfaces shoud be about .035.

The gap will get larger as the surfaces wear. Check the gap with a feeler guage. If it is out of specification it can be adjusted with shims. The wider the gap gets, the louder the clicking will get. Hope this helps, rangerj