I have a 2002 Mountaineer, V6. Has about 95,000 miles on it. I just noticed that my air conditioner is not working. The air may be just a little bit cooler than the outside air, but not by much. What steps should I take to troubleshoot. Could it be a fuse? Should I just recharge with refrigerant and see what happens? Thanks. Rob.

 

is the compressor turning on? if it is then you are prob low on r134a. if you compressor is not coming on then it could be a pressure problem or an electrical problem. check to see if the compressor is turning on then report back.

 

Well to start troubleshooting, I recommend you get a book on the subject, otherwise we will have to leave a long post and might leave stuff out. You will need a good manifold gauge set. Don't spend less than $80 on this vital piece of equipment. You will also need to determine if the compressor is even being commanded to turn on.

 

It would not be a bad idea to have the system evacuated and recharged after 6 years even if there is no leak. If a leak is suspected, dye can be added to pinpoint where it is coming from.

Check the obvious first though, is compressor cycling? Short cycling? How does the evaporator look?

 

If you are inexperienced with AC systems you can get in over your head pretty easily. Get a book and the gauges.

 

I agree on the getting in over your head, not so much in know how, but it takes some gear to diagnose and fix. Mine had similar symptoms, dealer evacuated, recharged system (with dye), kept it overnight then looked for leaks, found none. $190. An easy check to write (which at a dealer is rare).

A month later it works great. The only thing I didnt get was an explanation of why I wasn't getting cold air in the first place...

 

I bought a $29 kit from Advance Auto that included two cans of 134a. The cans had dye, oil, and sealer in them as well. My compressor is cycling on, then off in about ten second time intervals. The pressure while this cycling is happening goes from 25psi to 45psi, in step with the compressor turning on and off. Someone has suggested that I may need more coolant to keep the compressor from cycling so much. I am getting some cold air now. SHould be hot here in NJ this afternoon to see how it is working.

 

You have to be careful when using the $29 recharge system kit you are referring to. Without evacuating the system first, it is possible to overcharge the system at which point you can ruin the compressor. It is also possible to have too much or too little oil in the system which will also cause problems. Also, I wouldn't recommend putting any sealer in unless you know there is a leak and are willing to run the risk.

 

I had a problem like that and I was having my oil changed at Jiffy Lube and asked them to look at it. They checked it and the coolant was fine, there is a low pressure switch that went bad. The tech showed it to me and told me to go to the auto parts store and get it cheaper(he was right,they wanted 69.00 for the part there, 13.45 at the store) simple fix. One electrical connector and unscrew it from the system. You might have a qualified mechanic check it out for you and its an easy fix.

 

Strauss auto is running a $99 special to evacuate and refill air conditioner systems. Maybe I will just go have them do it. Meanwhile, I did put in refrigerant with the kit I bought. Everything seems to be working correctly now. I want to keep this vehicle for a few more years, so I may take your advice and have it done with the proper equipment.

 

Sixftpython, Exactly where is this low pressure switch located? I'm going to load some R12 into my 93 Explorer and I want to unplug this first.

 

For what R12 costs, you might want to consider converting to 134.

 

Hello Marragtop, I'm just lucky I guess because when R12 was replaced with R134, I bought a 30# canister of R12 at Sam's for $37. Unless it has leaked it should still have 26# or so left. My 3 cars then all used R12 so I knew it would be a good purchase.

What is R12 selling for these days?

 

Around $85 per lb. And you need a licence to buy it.

 

License only costs 15 or 20 bucks to get online.

FWIW, there is ABSOLUTELY no reason to evacuate and refill a properly working, sealed system. Makes about as much sense as rotating the air in your tires. Refrigerant does not wear out, there is no point to replace it.

OTOH, if it was low, it needs to have the leak identified, the remaining refrigerant recovered, the repair made, then to be properly evacuated and charged. You won't get all that done for $99. I suspect that the shop is using that price as bait to lure in customers for more expensive work.....

Billkean, Been a few years since I had to work on my old 93 'sploder. The switch is usually screwed into the accumulator can or a port on the hose very close to it.

Steve