I went to charge the ac today and when I turned the ac on , I noticed the ac compressor would start up then release every few seconds. I put the guage on the line and it read full, but im only getting slight cool air from the vents. Can anyone explain this?

 

You're probably low on refrigerant. Pull the connector from the pressure sensor switch (on the receiver/dryer) and temporarily short the connection with a short loop of wire...does the compressor now stay on?

I went through hell a few years ago with my A/C...I finally had to replace the compressor, receiver/dryer, orifice tube and all o-rings in the whole system. Works great now.

 

Was the compressor cycling when you where reading the gauge
?
That is the pressure that matters if you are usiing the handle type gauge that comes on the recharge can.Im not sure what is the normal low/high pressure is but the gauge on the recharge can shows what the low side should be.Also i found that if you just put the gauge to the low pressure service port it wont read right unless you are pressing it to the port.

 

I had an extra hose that came with the kit, which i cut and sealed in a bottle. When I connected it to the high, all that came out was air. So I guess the guage is reading it wrong. It must be low. I will try recharging it tomorrow and see what happens

 

My AC compressor does the same thing when it's charged. I do have a leak somewhere in my system though. When I finally get it up to the right pressure, the compressor will turn on, rapidly drop the pressure, then it will rapidly build back up. The pressure goes up to 45 psi and drops to about 25 psi, if I remember correctly. I checked the pressures against the pressures of my car, who's AC works perfectly, and they're the same. It just doesn't cycle nearly as fast, maybe about 3 or 4 times slower.

 

So you hooked it up to the high pressure service port?
Ive always been told to put it on the low pressure side service port.
Ejschultz- the pressure changes as the compressor cycles so if you are charging it or have the just on the port it will stay at whatever PSI in the system then when the compressor kicks on it will go down the when the compressor is off it slow rises till it kicks on again.

 

Man im burning up! Are the kits at autozone for 20 bucks pretty good,i think mine needs a recharge or something.

 

No, I meant to say low. It only fits on one. Im going to check it out tomorrow and see if I can empty it out and refill it.

 

Yes, I know the pressure changes as the compressor cycles. While the compressor is off the pressure builds up to about 45 psi then the compressor kicks on and the pressure drops to about 25 psi. The compressor turns off again at that point to allow the pressure to build back up. Those pressures are at about 70 degrees F ambient temp. My question is why does it cycle so fast?
It builds and drops about 4 times faster than a properly working AC system should.

 

There isnt enough refridge making it back to the compressor when the pressure drops to 25 it shuts off so the compressor will remain oiled. At pressures less than 25 it wont oil properly. It possible there just isnt enough refridge in the system,the orfice tube is partly plugged,and or there is too much oil in the system.