no coolling, cycling pressure values

[smoker_xr]

The refill kit "blue" gauge shows my pressure go up to 45 psi, something clicks, then it goes down to 25 psi (these are the upper and lower limits of the green range on the gauge).

Air temperature coming out of the center vent is outside air temp.

The time for each is about the same:
pressure builds up in about 3 seconds to get up to 45 psi
pressure reduces in about 3 seconds to get down to 25 psi

Outside air temp doesn't seem to effect this timing.

I tried increasing the idle speed, but saw no change in temperature.

91 Ranger XLT
2.3L, 4 cyl, 5 spd manual
110,000 miles
R-134 retrofit kit installed

Thanks,
Ken

 

[MAKG]

Sounds like fast cycling, perhaps due to undercharging (or maybe it's just cold there).

But you can't really know based upon the low side alone. The only thing you know is that the pressure switch appears to be set sensibly.

It's not easy to diagnose a system you don't understand. That's what A/C techs are for.

 

[wvcat]

I filled 3 rangers today at our meet I put 2 cans in each. The capacity for a ranger is 1.75 lbs of freon or 28oz. Thats a little over 2 cans if completely emty. I would say to add another can

 

[thegoat4]

Ignore vwcat's advice until you know what's going on.

The clicking is from your compressor clutch coming on and off. When it's on, your pressure on the low side (where your gauge is) will fall. Once it gets too low, the compressor will disengage and stop pumping, allowing the system to equalize. Pressure on the high side bleeds over to the low side and causes the reading on your gauge to come up. Once high enough, the compressor comes back on and starts pumping again.

Feel your ac lines. The high side (line from the compressor to the condenser in front of the radiator, the condenser itself, and the line from the condenser to the evaporator on your firewall) should feel hot. You'll get a slight temperature fall across the condenser core, but not a whole lot. Since you don't have a high side gauge, that's the best you can do. If none of that feels hot, yeah, you're probably low on freon. On the other hand, if part of it feels hot, but then the rest feels cold, you have a blockage right where it changed temp. If it's hot like it should be all the way through, then you probably have some sort of problem within the dash, like a dirty evap core or a stuck duct door.

And by hot I mean it'll blister your fingers if you're not careful.