94 Legacy SW 250t
When I've been driving around for a while and I turn of the engine, there is a knocking sound which eventully slows down and stops.
I've looked under the hood and its the compressor still turning.
Why is it doing this and how can it be fixed.
Thanks
Air Conditioning Compressor knocking
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- Vikash
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I'm sorry to tell you that your compressor is probably on its way out. They usually start knocking when they've been starved of lubrication. Left that way, eventually they fail completely and send bits of metal all through the system.
It might be early enough that you could at least temporarily resolve the problem without replacing the compressor -- have the system evacuated, flushed, and recharged with new oil as well as refrigerant. Or be ghetto and try an "oil charge."
It might be early enough that you could at least temporarily resolve the problem without replacing the compressor -- have the system evacuated, flushed, and recharged with new oil as well as refrigerant. Or be ghetto and try an "oil charge."
"Just reading vrg3's convoluted, information-packed posts made me feel better all over again." -- subyluvr2212
It's toast. There is nothing you can do to salvage it. It's already putting metal shavings into the system.
Just drive it until the compressor seizes. At that point, remove everything, clean it THOROUGHLY, and put a new compressor in.
I've been through 3 used compressors, and finally put in a new one.
Just drive it until the compressor seizes. At that point, remove everything, clean it THOROUGHLY, and put a new compressor in.
I've been through 3 used compressors, and finally put in a new one.
Josh
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
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- Vikash
- Posts: 12517
- Joined: Sun Nov 03, 2002 2:13 am
- Location: USA, OH, Cleveland (sometimes visiting DC though)
- Contact:
If the compressor is not running, it won't cause any more damage than whatever's already happened.
The compressor runs in A/C, MAX A/C, DEFROST, and DEF/HEAT modes. You can disable it by disconnecting the compressor clutch or pulling the relays from the fuse box.
The compressor runs in A/C, MAX A/C, DEFROST, and DEF/HEAT modes. You can disable it by disconnecting the compressor clutch or pulling the relays from the fuse box.
"Just reading vrg3's convoluted, information-packed posts made me feel better all over again." -- subyluvr2212
You can also wire in a "kill" switch to the compressor, so that when the Defrost is on outside air that is not chilled can flow.
At WOT there is an automatic shut off switch, but a manual over ride is a worhwhile option
At WOT there is an automatic shut off switch, but a manual over ride is a worhwhile option
Subtle (normally aspirated engines suck):
05 Legacy GT Wagon with Cobb chip.
62 Alfa Romeo Spider- had a 1.6 L with 80 hp, now 2 L with 160 torque. Curb weight 2050 lbs.
93 Leg Twgn fmic, vf34, etc. ((sold))
05 Legacy GT Wagon with Cobb chip.
62 Alfa Romeo Spider- had a 1.6 L with 80 hp, now 2 L with 160 torque. Curb weight 2050 lbs.
93 Leg Twgn fmic, vf34, etc. ((sold))
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- Third Gear
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