A/C Compressor

[G-Unit]

When I turn on the A/C, the end of the compressor where the belt is, stops spinning, then catches again, then stops, and so on. Each time it does so, it makes a clicking noise. What is the problem?

G-Unit

 

[Glacier991]

the clicking is the noise the compressor makes when the clutch engages, nothing wrong. The system will kick in if there is more than approx 40-45 lbs pressure in it, but once operational it quickly on the suction side drops that to 27 lbs wherein the low pressure switch causes the clutch to disengage. Not running, the low side starts to equalize to the high side (which it will do) and once it's over the 40-45 lbs the clutch kicks back in, and so on and so forth. Click Click Click. The cure? Add refrigerant to the system. You are low.

 

[luckyco]

My 99' Sport is experiencing the same symptom. I was hestitant to fill it since the instructions on the refill didn't mention the oscillating pressures, so I was worried something might be wrong. Will pressures balance out as you begin to add refrigerant?

Thanks

 

[Glacier991]

it will continue to cycle, but stay on longer and longer... when the compressor disengages the pressure in the low side will rise as it equalizes towards the high side. When the compressor comes back on the pressure will drop until the low pressure cutoff is actuated. How often it cycles depends on the relative state of charge, and even with the correct charge will cycle depending on ambient temps, condensor cooling and cabin temperature. Rapid cycling is a red flag for a low charge state. (Except during periods of cold weather)