75psi on high and low side

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getterdun
Posts: 1
Joined: Sat May 19, 2018 4:57 pm

75psi on high and low side

Postby getterdun » Sat May 19, 2018 5:09 pm

Vehicle: 2005 Acura RL
Problem: Gauge reads 75psi on both high and low side after adding 1 can of R134a
Prior action: Have replaced compressor twice and expansion valve once
* First compressor replacement was because original one was leaking. This was a cheap Chinese compressor.
* Second compressor was after installing first replacement the pressures were equal: same as above. This is an expensive Denso compressor.
* At this point, the only thing I knew to do was to replace the expansion valve. But, even after this, the pressures are the same.[/list]

At a loss for what to do next. Will appreciate any help. Thanks.
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Cusser
Posts: 361
Joined: Sun Apr 24, 2016 6:29 am

Re: 75psi on high and low side

Postby Cusser » Sat May 19, 2018 8:45 pm

It sounds like the AC clutch on the compressor is not engaging. Is the CENTER part of the compressor actually turning, or just the outer rim of the pulley?
JohnHere
Posts: 105
Joined: Sun May 13, 2018 10:20 am
Location: South Carolina Upstate

Re: 75psi on high and low side

Postby JohnHere » Sat May 19, 2018 9:03 pm

I would approach this by first recovering the refrigerant that's in it now, pulling a good vacuum for at least 30 minutes, and weighing-in the factory-specified charge of 19.0 ounces of R134a. Then take LP and HP gauge readings at an engine speed of 1,800 RPM with the A/C system on and report the pressures here. Leak-checking the system at this point is also a good idea since you thought the system was low on refrigerant and you added a can (hopefully without any sealer or enhancers in it). The 75 PSI readings you have now sound to me like static pressures (A/C system and engine off).
JohnHere
Posts: 105
Joined: Sun May 13, 2018 10:20 am
Location: South Carolina Upstate

Re: 75psi on high and low side

Postby JohnHere » Sat May 19, 2018 9:08 pm

If you have only about 12 ounces in it (one can), it is way too low. And as Cusser alluded to, the compressor won't engage.

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