1993 AC Problems

[camREEtrDEE]

So I picked up a 1993 Explorer XLT 4x4 without functioning air conditioning. The compressor clutch won’t engage at all when the AC is pressed. Here is what I have troubleshot so far.

1. The system was near empty so I charged it up to full with coolant.

2. Tested for leaks, and there are none (that I can see anyways.)

3. Jumped the compressor straight to the battery to test the clutch, and it engages fine.

4. Started the truck, and unplugged the low pressure switch on top of the accumulator and jumper-ed it with a piece of wire. The compressor will run now, but only for 4 seconds before shutting off. If the jumper was wiggled it turned the compressor on again for another few seconds. Chalking this up to the jumper wire not getting a great connection on the tiny plug holes, I replaced the low pressure switch.

Now that the switch is replaced and everything is back to plugged in, I am back to having nothing. I have tried turning the adjustment screw 1/4 turn counter.clockwise to adjust pressure and still nothing. Struggling as to what the issue is. I’m thinking about ordering the female plug/wires for the low pressure switch, since mine is pretty nasty. (Green goo-like corrosion) But I don’t want to be grasping at straws. The compressor is fairly new and relatively clean, as it has a sticker for R134a, so I’d assume it was already replaced, along with proper fittings. I know summer is almost over but these Texas 112 degree days suck. Lol.

 

[Motorhogman]

I suggest this site for great tech info and troubleshooting. . Did you evacuate the system before charging to see if it holds vacuum ?

AC pressure gauge readings

How to diagnose car AC pressure gauge readings

ricksfreeautorepairadvice.com

 

[mcfixstuff]

Given the low cost nature of the AC parts on the explorer, I recommend just replacing the system. EVERYTHING new on mine was like $400. When you do that , make sure you use a red orifice tube. So many mixed responses on forums regarding which color to use. Only use red. No exceptions. If the compressor keeps cycling at low temps, adjust the cycling switch screw. Took many trial and error to figure out the red, non adjusting orifice tube was the way to go.

To answer why your system keeps cycling despite your low pressure switch being bridged, I'll assume maybe the high pressure side is too high because of a trashed compressor, or trash in the condenser.

Rent some gauges at autozone, and force the compressor on to look at the gauges.

 

[Pete Deering]

So I picked up a 1993 Explorer XLT 4x4 without functioning air conditioning. The compressor clutch won’t engage at all when the AC is pressed. Here is what I have troubleshot so far.

1. The system was near empty so I charged it up to full with coolant.

2. Tested for leaks, and there are none (that I can see anyways.)

3. Jumped the compressor straight to the battery to test the clutch, and it engages fine.

4. Started the truck, and unplugged the low pressure switch on top of the accumulator and jumper-ed it with a piece of wire. The compressor will run now, but only for 4 seconds before shutting off. If the jumper was wiggled it turned the compressor on again for another few seconds. Chalking this up to the jumper wire not getting a great connection on the tiny plug holes, I replaced the low pressure switch.

Now that the switch is replaced and everything is back to plugged in, I am back to having nothing. I have tried turning the adjustment screw 1/4 turn counter.clockwise to adjust pressure and still nothing. Struggling as to what the issue is. I’m thinking about ordering the female plug/wires for the low pressure switch, since mine is pretty nasty. (Green goo-like corrosion) But I don’t want to be grasping at straws. The compressor is fairly new and relatively clean, as it has a sticker for R134a, so I’d assume it was already replaced, along with proper fittings. I know summer is almost over but these Texas 112 degree days suck. Lol.

By you stating It ran for 4 second and stops. Tell me it low on r134