Air Conditioning problems

[dougmac]

If you are seeing 80 psi low side and 90 high, the compressor is not pumping refrigerant. If the clutch is engaged and the belt is turning, there is an internal problem with the compressor. Possibly a valve that has failed and is intermittently sealing.

 

[blackhawk]

Yes, my hoses are 6ft long so I ran then inside so I could watch them.
Blackhawk, I have bypassed the switch and with the gauges hooked up ran inside the cab the pressures are all over the place. The low pressure still rises and the high pressure still falls for a few seconds and then goes back to normal for a few seconds and the cycle continues. Only the compressor is constantly running.

I thought maybe the low pressure line may be the culprit but the more I think about it, if there was a partial clog, wouldn't it be acting up all the time?
I may just break down and buy a new compressor. I've exhausted everything with nothing that works.
Can't just sit at idle for cold air

Hi Corey, Having the compressor constantly running....Is the cold air constant too or not?

 

[tjkj2002]

Yes, my hoses are 6ft long so I ran then inside so I could watch them.
Blackhawk, I have bypassed the switch and with the gauges hooked up ran inside the cab the pressures are all over the place. The low pressure still rises and the high pressure still falls for a few seconds and then goes back to normal for a few seconds and the cycle continues. Only the compressor is constantly running.

I thought maybe the low pressure line may be the culprit but the more I think about it, if there was a partial clog, wouldn't it be acting up all the time?
I may just break down and buy a new compressor. I've exhausted everything with nothing that works.
Can't just sit at idle for cold air

That proves the compressor is bad if indeed the compressor is turning when that happens.

Replaced 4 compressors so far this week alone for that very same issue.Been seeing a lot of plugged condensers also lately along with overcharged systems,plugged systems(autoparts store kits with stop leak added in the R134a),and over oiled systems.

You need to replace the orifice tube and receiver/dryer with the compressor and since 1994 you can not flush the evaporator or condenser due to design.

 

[CoreyH]

I should have stated that while driving the compressor kicks on and off. I had said that the compressor was constantly running when I bypassed the clutch switch. So when I plugged it back in, at idle, it works properly. Blows ice cold. Only when driving does the pressures go out of wack. So one time I bypassed the switch and took it out for a drive and the pressures still went crazy with the compressor running. When the switch is plugged in, the pressures still go crazy.
Just wondering if a slightly plugged orifice would cause it to run perfect at idle and mess up while driving, or if the compressor is going out then why does it work fine at idle. In park at idle, it works perfect.

 

[tjkj2002]

I should have stated that while driving the compressor kicks on and off. I had said that the compressor was constantly running when I bypassed the clutch switch. So when I plugged it back in, at idle, it works properly. Blows ice cold. Only when driving does the pressures go out of wack. So one time I bypassed the switch and took it out for a drive and the pressures still went crazy with the compressor running. When the switch is plugged in, the pressures still go crazy.
Just wondering if a slightly plugged orifice would cause it to run perfect at idle and mess up while driving, or if the compressor is going out then why does it work fine at idle. In park at idle, it works perfect.

A partially plugged orifice tube would make the high side pressure go way high,like 400psi+, not drop to ambient temp.

 

[blackhawk]

Well, the same symptoms that mine... do you thing the a/c cycling switch is not working properly?

 

[blackhawk]

Well, finally I replaced the a/c cycling one month ago and now I got my a/c working fine!!

Sympthoms:
The air starts off cold and then gets hot, then cold, then hot….
It gets cold in idling mode and gets hot (compressor disangages after driving +60 km/h for 15 minutes).