HELP!!! A/C problems........

Last year my a/c was working great, this year its not cooling like it did. I went to walmart and bought a r-134a service kit. Well, I hooked up the gauge and its a hair over 45psi. The chart says to make sure its on the low-pressure(only fits on one side) and it may be overcharged and not to add refrigerent. Any idea's on what to do? I'd rather not bring it to a shop. thanks!

UPDATE: It turns out the a/c wasn't working at all. The compressor clutch isn't getting power. I put a jumper wire from the battery to the clutch and she works great. Any idea's why its not getting power?

Wonder if its so low on coolant the low pressure switch wont let it get power. You can turn on your ac pull the harness from the switch jump it briefly and see if your compressor clutch engages. If it does then you either need to charge the system or the switch is bad. Most likely youve got a leak.

Where is the switch and can I test it?

When the coolant gets low the switch, which is in that silver tower, prevents the compressor from cycling on. Go pick up a small can of 134a with leak detector and hook it up. After adding that can and you system was borderline, R134a coolant level wise, the compressor should start to cycle on and off. If it does you can add another can to get by or have it repaired. According to my 98 FSM it says that if the compressor cycles more than 5 times perminute on high/max ac then the level is low. If the small can starts it operating but not quite past the 5 cycles per minute it is still low. The other method is to go pick up the 3 gauge set for ac service for about $90 w/hoses and hook up according to the FSM, that will give you a more detailed reading or the coolant level.
Personally I have noticed that my return line gets real hot when the level is starting to get low and the low pressure side does not sweat so much. I generally end up adding an 8oz can at the beginning of the season and another around the end of august. Yes, I have a leak but have not been able to afford the downtime to have it fixed. I have been searching around for a freon sniffer on ebay and a couple of other places to try to find my leak and fix it myself, my gut feeling is that it is one of the plastic joints.

Good friend of mine who's an AC&R tech says that most of the time the leak will be the valves. The little rubber seal in them starts to leak.

Thats why I want the sniffer, I figured that we've spent enough money with my wifes car at the repair guy we've used for years. Asked him if I could use it for a few minutes to see if I could spot a quick leak and you'd think I asked to borrow his toothbrush, geeze. Said he'd check it but would have to charge me, he can fix his own computer problems from now on. Anybody know a cheap source for a 134 sniffer ??? Looking to spend only ~$50.
When I do check it I sure hope it does not beep near any of the interior vents

OK, tried adding r134a but I don't think I was doing it right? Should the a/c be on when doing this? I had the jumper on making the clutch going round and the 134a was coming out where the can & valve meets. The air comes out ice cold with the jumper hooked up......

The a/c is still not working......any idea's? Was I putting the 134a in right by jumping the clutch to make the a/c work? Thanks in advance!

there is a a/c clutch relay... see if it is good.


I think it is the one on the far left(located on the passenger side fender, should be a row of four of them...) swap it out with another one preferably the one on the far right, that is your 02 sensor heater relay... if you swap and it works, you found your problem

There is no need to jump the compressor when filling it with freon. All you do is hook up the hose and put the can on it and open it up. When you get enough freon in it it will start cycling by itself. If you put in freon and didn't notice leaks and it didn't start working after the first can you probably need a new relay or low pressure switch. You can try another can but I wouldn't put in ore than two cans. You can take the plug off of the low pressure switch and jump it there (after trying to put freon in it) if it comes on when jumping it there the pressure switch is bad. If it doesn't come on then the relay is bad. If you replace the relay and the switch and it has enough freon then you have a different wiring problem. I just went through all this with my jeep and my truck. My problem was freon. On my dads truck the pressure switch was bad.

OK, I checked the relay by swaping with a good one........same thing, no a/c.

I'm thinking I didn't put the first can of 134a in right. I thought the clutch had to be working for it to suck it in. The gas just came out by the top of the can. I guess i'll try one more can without jumping the clutch.......thanks for your help!

mike

It should not come out anywhere, it should go into the system. Tehcnically you don't really need the engine running if it's really low, the only reason I can see to run it is to start cycling the freon once it gets past a certain level and the compressor starts compressing and pumping.
On my 98 I just start up the engine, screw the hose on the adapter, hook it up to the low pressure schrader valve, run the puncture screw down thru the cap, back it out all the way and let it pull/push the freon in. Other than the can sweating and the compressor staying on longer and longer and the can getting lighter you should see nothing else happening.
Hmmmm, did you use one of those cans with the hose already connected. I tried a couple of them and they leaked more out than they got in the system.
Once it get some spare pocket change I'll pick up the 3 gauge 3 hose set. Seems like that would be alot more informative than the can and hose on I use plus sams sells the 135 in propane sized cannisters for a alot cheaper then those 8oz cans cost.

Just went out and used the gauge from the recharge kit and it shows about 55psi and the clutch still will not go on without using a jumper wire. The chart says up to 45psi only.....so i'm thinking I need the pressure switch. Is there a way to test it?

multimeter

Take your multimeter and check for volts on both sides of the switch. Ditto for the relay. If you're getting volts out of both sides then look for a broken wire. My Haynes shows an electronic thermostat in the circuit also. Just go hand over hand down the wiring. I would go backwards from the compressor until you find power. Good luck.

WOO HOO! Found the problem........ It was just a stupid fuse. One of those small ones left of the relays. She now works like a champ! Thanks for all your advice!