A/C only works when you rev the engine to about 2500 rpm
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A/C only works when you rev the engine to about 2500 rpm
Like the title says the A/C only works when you rev the engine to about 2500 rpm. I have a manifold gauge and at idle speeds the low side was around 70-90 psi, and the high side was about 150 psi. When you rev it up to about 2500-3000 rpm, the low side goes to 0-10 psi and the high side steadily climbs until it gets to 200 to 250 psi and the low side go's to 30 psi. I think it needs a new compressor. I just wanted a second opinion before I bought one.
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Re: A/C only works when you rev the engine to about 2500 rpm
Spend some time checking your ac clutch. Your pressures seem about right at high speed which if the compressor was actually failed you would be seeing much lower high pressure.
Now if the clutch is starting to slip, at low revs not enough force to build up pressure could occur.
Tools and technique needed, but possible you ust need to reset the air gap, read up on how to measure it.
Now if the clutch is starting to slip, at low revs not enough force to build up pressure could occur.
Tools and technique needed, but possible you ust need to reset the air gap, read up on how to measure it.
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Okay I checked the air gap with a feeler gauge .016 of an inch was kinda tight but would fit. The compressor stays on unless you turn the A/C off. I think because its not building enough pressure. At idle speeds the low was 70 psi and high was 150 psi when I rev it up low go's down to 20 psi and high up to 250 psi. I think It could be a weak compressor. Any thoughts?
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From what I can find the clearance for the compressor clutch should be 0.5 +/- 0.15 mm (0.020 +/- 0.006 in.). Sounds like you're within that spec.
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From: Avera,GA
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I'm about 90% positive that the A/C compressor is worn out. Because I saw in a YouTube video that if you can easily turn the compressor with a finger that the compressor is worn out. I can turn mine with one finger.
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Now you get to worry that all your AC lines, condenser, evaporator ect might be coated in fine metal particles that would love to shorten the life of your new compressor in a hurry.
Honda dealer has a filter I think they use when they replace a unit.
Honda dealer has a filter I think they use when they replace a unit.
If you think a good mechanic is expensive, try hiring a bad one
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The pressures look to me like a bad compressor, pumping efficiency is just no good at low RPM..... worn out seals or whatever inside the unit. Next concern would be checking the system internals for contamination, that gray metallic film that coats the insides of the system as the compressor slowly wears itself out or grinds itself to death.
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