How often should the a/c cycle while cruising? (Other vehicles)

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squaredeal91

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On a jeep liberty 3.7l v6.
The compressor stays on pretty good while sitting and idling. Just replaced bad electric fan. While cruising the compressor cycles on and off pretty frequently. I added a little and still did it but seemed to delay the start of the frequent cycling. Any thoughts on if it should for the most part stay on while cruising. Roughly 1500 rpm.
 

squaredeal91

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Added this light to watch while driving. Comes on with the compressor.
 

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fast 99

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This is general information not specific to a Liberty.

Clutch cycles to prevent condenser freeze up and if refrigerant is low protect the compressor. In order to diagnose it correctly system will need the correct charge. 134A is very sensitive to either over or under charge. After doing that will need data for system pressure and correct pressure values.

Could be incorrect charge, an internal restriction or bad cycling switch if indeed there is anything wrong. We have seen many cases where cars come in after the owner added a can or 2 of 134A. All we have to do to many of those vehicles is discharge and add correct volume. 134A systems do not require near as much refrigerant as the old R12.
 

squaredeal91

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5.9 Cummins 12 valve
This is general information not specific to a Liberty.

Clutch cycles to prevent condenser freeze up and if refrigerant is low protect the compressor. In order to diagnose it correctly system will need the correct charge. 134A is very sensitive to either over or under charge. After doing that will need data for system pressure and correct pressure values.

Could be incorrect charge, an internal restriction or bad cycling switch if indeed there is anything wrong. We have seen many cases where cars come in after the owner added a can or 2 of 134A. All we have to do to many of those vehicles is discharge and add correct volume. 134A systems do not require near as much refrigerant as the old R12.
Thank you fast 99, I added a gauge on the hood to go with the light and was able to test drive while watching both. I watched it and adjusted it to a good acceptable level and it stayed around 55ish# fluctuating up and down 5-10# depending on what speed and work the engine had to do.
did some on off highway in town and idling in parking on side of the road. Stopped at a lemonade stand lol and seemed to do really good.
My biggest question is how much pressure isdangerous for the low side.
 

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fast 99

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My biggest question is how much pressure isdangerous for the low side.

Varies

55 lbs sound a little on the high side, overcharge?

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fast 99

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Air flow and ambient temps, have a lot to do with pressures. If you want to verify that pour a little cold water on the condenser with gauges hooked up.
 

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