Last week, while driving to NJ to pick up a header, I noticed that I was loosing more power than usual with the A/C on. When I kept the throttle steady, I started to feel the car surging, and the air coming from the vents getting warmer and warmer. I pulled over, popped the hood, and saw the compressor clutch engage... disengage... engage... disengage over and over. I thought that maybe it was due to a loss in refrigerant, so I left the A/C off for the rest of the trip.
I tried it again the next day and it worked properly so I didn't think much of it, but the problem returned later in the week.
On Sunday, I decided checked the pressure in the system, and it was slightly low on the generic gauge I have, cycling between 20 and 35psi. I know there's a small leak at one of the fittings, so I just topped it off and let it go.
Today I noticed a massive loss in power when I turned the A/C on, I had to be around 30-35% throttle to maintain speed, where I'm usually fine with 17-19%. The A/C barely puffed any cool air, and after a minute or so of no power, the CEL light up solid. I did what any self respecting gearhead would do, and I decided to slap it around a bit and romped on the gas pedal. The CEL went away, only to return after a few minutes of normal driving.
I was going to take a video of the compressor acting up and the gauge readings, but the A/C was finally acting normal just idling in the driveway. I did however notice that the low pressure line from the evaporator and the compressor was ice cold and was collecting condensation. I checked the pressure and it's cycling between 25 and 40psi, but again the compressor is acting normal. I haven't had the chance to check the pressure yet while the system is acting up.
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I'm coming to the conclusion that the refrigerant isn't boiling completely in the evaporator, the loss of power is because the compressor is trying to compress liquid refrigerant, and the CEL is just a side effect.
What I don't understand is why the refrigerant isn't being held in the evaporator long enough to boil. I was wondering if there is too much refrigerant in the system. The pressure is within the generic range on the gauge, but maybe Subaru's run at lower pressures? Any advice or suggestions?
C/N: Read the last two paragraphs and look at the pictures.
I tried it again the next day and it worked properly so I didn't think much of it, but the problem returned later in the week.
On Sunday, I decided checked the pressure in the system, and it was slightly low on the generic gauge I have, cycling between 20 and 35psi. I know there's a small leak at one of the fittings, so I just topped it off and let it go.
Today I noticed a massive loss in power when I turned the A/C on, I had to be around 30-35% throttle to maintain speed, where I'm usually fine with 17-19%. The A/C barely puffed any cool air, and after a minute or so of no power, the CEL light up solid. I did what any self respecting gearhead would do, and I decided to slap it around a bit and romped on the gas pedal. The CEL went away, only to return after a few minutes of normal driving.
I was going to take a video of the compressor acting up and the gauge readings, but the A/C was finally acting normal just idling in the driveway. I did however notice that the low pressure line from the evaporator and the compressor was ice cold and was collecting condensation. I checked the pressure and it's cycling between 25 and 40psi, but again the compressor is acting normal. I haven't had the chance to check the pressure yet while the system is acting up.
I'm coming to the conclusion that the refrigerant isn't boiling completely in the evaporator, the loss of power is because the compressor is trying to compress liquid refrigerant, and the CEL is just a side effect.
What I don't understand is why the refrigerant isn't being held in the evaporator long enough to boil. I was wondering if there is too much refrigerant in the system. The pressure is within the generic range on the gauge, but maybe Subaru's run at lower pressures? Any advice or suggestions?
C/N: Read the last two paragraphs and look at the pictures.
