AC Problem - 2003 Mercury Sable

AC Problem!

I recently acquired a 2003 Mercury Sable from a friend and there is a problem with the air conditioning. The car has digital controls. I select the Max AC button, turn the temperature all the way down (60) an the fan all the way up, but it only blows warm air. I can hear and see the AC compressor cycling fairly quickly. The clutch (I think) engages for about one second and it will reengage after about 5 seconds, but again, it only says engaged for about one second.

What could be the problem? I’ve read the AC system might not have enough pressure and needs to be recharged. Or… the orifice tube is clogged, bad AC pressure switch, or the actuator that closes the heater door might be disconnected.

How quickly should a properly functions AC compressor cycle?

The car was not driven much over the past year or two as it was my friend’s grandfathers.

I may end up taking it to a shop but I don’t want to get ripped off. How should I approach this?

I appreciate your input!

I’ll wager ; low on freon.
But don’t just start adding in freon, it needs to be the right amount of charge.
PLUS . . while it was sitting , some leaked out. A dye needs to be added first to see which o-rings need replaced.
My 92 Explorer used to do that and a couple of 50 cent orings fixed it.

I can almost guarantee you have a low refrigerant

The compressor engaging, but only for a very brief time, then disengaging, without cold air, is called short cycling

Thank you ken and db! I’ll tell the shop my AC compressor is short cycling and I believe it’s low on freon.

They will charge me $35 to look at the AC, so I hope they agree to the recharge and hopefully that works and they don’t come back saying I need a new AC compressor. Appears to be a $600-800 repair.

By coincidence some years back I got a Sable loaner when doing some work in Texas. It was hot and the A/C did not work well. Sure enough it was low on refrigerant and a $50 visit to a shop got me going again.

Check for leaks. If the car was used a lot in a hot climate the compressor might be worn out.

AC repair on a 13 year old car like that can get expensive, and fast. One part failing can cause other parts to fail, and you sometime have to replace or otherwise renew most everything to get functional AC again. Hopefully it’s just the coolant charge. If this were my car I’d be inclined to seek out a well recommended AC specialist shop.

Hans-Telling a shop what they need to do to fix your problem is never a good idea. You are paying them 35.00 to look at it and after they do you can decide if you want to take the recommended solutions or not. Just make it clear no repairs without approval.

At 14 years of age I would not be surprised if the refrigerant is low and due to a leaking compressor shaft seal.

I will also suggest that if a refrigerant charge is performed that some refrigerant oil be added. With the loss of refrigerant, oil in the system is also lost.
As time goes by and the system is constantly being recharged without the addition of oil there comes a point when the compressor may make a big bang and that will be the end of that.