Okay folks ... talk to me like I'm five years old !!

I mean FIVE YEARS OLD !

I'm not very knowledgeable at all when it comes to AC problems. Anyhow, here goes!

I have a 1997 Jimmy SLE 4WD W. The AC is only slightly cold. It seems cooler than outside air ... but not much.

I checked the fuses - all good. I bought a 134a recharge kit. It also has oil, dye, freon - all-in-one, and a pressure gauge. The pressure was low. I gave it a burst of freon and got it up to normal pressure (approx 50-55psi). There seem to be no visible leaks.

Still not much difference ... maybe just a little ...

When I gave it a burst of freon, the compressor clicked briefly. The pressure shot back down to maybe 15 psi and then gradually built up to 55psi. This took about 10 seconds. Then, again, the compressor stopped clicking and the pressure shot down to 15psi. Again it built to 50-55psi.

What I'm not sure of is ... what is a "normal' compressor cycle? How long should it click? Does the clicking mean its working and doing its job? Should it be clicking all the time that the AC dash-control is on?

I don't think it is the blender vent. The heater is blowing consistent hot air. Also, I "hear" the blenders working when I switch from heat to AC.

I've read in previous posts about "jumping" or jumper wires to check the low pressure switch on the accumulator. Can someone describe exactly how to do this? I don't want to short something out! Talk to me like I'm five years old! What kind of wire? Connect a wire from the low pressure switch to WHERE?

Also, I've read from previous posts about checking the relay. How do I check it?

Other ideas?

Any help would be appreciated. Thanks.

I am not totaly positive if this is your problem sure sounds like it to me, but from another car that i had a similar problem so i replaced the compressor and it fixed my problem, good luck

Okay folks ... talk to me like I'm five years old !!

I mean FIVE YEARS OLD !

I'm not very knowledgeable at all when it comes to AC problems. Anyhow, here goes!

I have a 1997 Jimmy SLE 4WD W. The AC is only slightly cold. It seems cooler than outside air ... but not much.

I checked the fuses - all good. I bought a 134a recharge kit. It also has oil, dye, freon - all-in-one, and a pressure gauge. The pressure was low. I gave it a burst of freon and got it up to normal pressure (approx 50-55psi). There seem to be no visible leaks.

Still not much difference ... maybe just a little ...

When I gave it a burst of freon, the compressor clicked briefly. The pressure shot back down to maybe 15 psi and then gradually built up to 55psi. This took about 10 seconds. Then, again, the compressor stopped clicking and the pressure shot down to 15psi. Again it built to 50-55psi.

What I'm not sure of is ... what is a "normal' compressor cycle? How long should it click? Does the clicking mean its working and doing its job? Should it be clicking all the time that the AC dash-control is on?

I don't think it is the blender vent. The heater is blowing consistent hot air. Also, I "hear" the blenders working when I switch from heat to AC.

I've read in previous posts about "jumping" or jumper wires to check the low pressure switch on the accumulator. Can someone describe exactly how to do this? I don't want to short something out! Talk to me like I'm five years old! What kind of wire? Connect a wire from the low pressure switch to WHERE?

Also, I've read from previous posts about checking the relay. How do I check it?

Other ideas?

Any help would be appreciated. Thanks.

Did you fill the system using the right port?

It should be the one on the tall metal cylinder type thing.

Also, did you have your AC on to max and the fan on full blast when you were filling it?

Yes and yes.

Yes I'm 99 percent sure I had the correct port (this is about the only thing that the Haynes manual is helpful at!) -- also, the only fitting that works ...

Yes, I had the engine running, fan on high, AC on max ...

what from here ... ???

I've heard that relay malfunctions are rare ...

... not sure of the relationship between AC system pressure and refrigerant level ... does high AC system pressure also equal high refrigerant level ... ???

what from here ???







Did you fill the system using the right port?

It should be the one on the tall metal cylinder type thing.

Also, did you have your AC on to max and the fan on full blast when you were filling it?

How much refrigerant did you use? Does the clutch kick in and out rather quickly?

Yes and yes.

Yes I'm 99 percent sure I had the correct port (this is about the only thing that the Haynes manual is helpful at!) -- also, the only fitting that works ...

Yes, I had the engine running, fan on high, AC on max ...

what from here ... ???

I've heard that relay malfunctions are rare ...

... not sure of the relationship between AC system pressure and refrigerant level ... does high AC system pressure also equal high refrigerant level ... ???

what from here ???

Go check the pressure again with all the fan and AC setting on max and make sure it is in the good area.

Also, make sure your coolant is up to level.

So the coolant is up to level. Coolant temp is fine.

I previously added about 70% of one 14 can of 134a/oil/dye all-in-one.
I stopped at 70% because the pressure read approx 55psi (into the "full" zone). However, today I finished off the remaining 30%. It allowed me to do this without the pressure rising.

I'm beginning to think that I may just need a little more refrigerant. I'm hoping this is the case.

So the question for the experts is: what is the relationship between an AC system's pressure and refrigerant level? Is is possible to have normal pressure and yet low refrigerant?

The compressor now cycles regularly. Clutch spins for 2 seconds and then off for 10 seconds. Then 2 then 10, etc, etc. Is this normal?

My last refrigerant charge was approx 2 1/2 years ago. It ran cold as ice for that long.

I've heard that refrigerant in a normal system is never consumed and does not breakdown like oil. Is this true? Refrigerant loss over 2 1/2 years would then be a really slow leak.


Go check the pressure again with all the fan and AC setting on max and make sure it is in the good area.

Also, make sure your coolant is up to level.

If its going on for two seconds and off for ten, you need a little more refergent. Its has to cycle on for a little more than two seconds to generate any type of good cooling. What type of guage are you using, the one that comes with those kits? If its one of those kit gauges, it should not drop up and down so fast. This indicates you still need more refergent. It will be full when the a/c compressor engages stays on for a while and builds, shuts off and drops again not too fast.

If its going on for two seconds and off for ten, you need a little more refergent. Its has to cycle on for a little more than two seconds to generate any type of good cooling. What type of guage are you using, the one that comes with those kits? If its one of those kit gauges, it should not drop up and down so fast. This indicates you still need more refergent. It will be full when the a/c compressor engages stays on for a while and builds, shuts off and drops again not too fast.

THANKS ALL ! Looks like I just needed more refrigerant. I bought another bottle and put about 3 or 4 more ounces in ... now I'm ICY COLD ... BBRRRRRRRR !!!!!!!

Okay folks ... talk to me like I'm five years old !!

Thanks.

Be careful not to use that line around Michael Jackson!