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Negative low side pressure with compressor engaged?

Forest337 on Mon July 07, 2008 5:21 PM User is offline

Year: 1995
Make: Honda
Model: Accord V6
Engine Size: 2.7l
Refrigerant Type: 134a
Ambient Temp: 85F
Pressure Low: +22, -5?
Pressure High: ?

Girlfriend has been having some trouble with her AC, so I hooked up my gauges to get a better idea of what is going on. First problem: my high-side 134a adapter doesn't fit. Would a 90's V6 honda be a special fitting? Anyway, with the a/c off, the low side reads 22lbs. With the compressor engaged, it reads -5lbs. Am I doing something stupid here? I've never had that happen before. a/c is producing some "cool" air. Suggestions?

mk378 on Mon July 07, 2008 5:37 PM User is offline

You need to measure the high side pressure too. It could be a blocked expansion valve or a system that has leaked down. The high side would tell.

All factory 134a systems have the same standard fittings. Some cheap manifold gauge couplers are made to a bad tolerance and they don't fit on all cars though.

Chick on Mon July 07, 2008 8:58 PM User is offlineView users profile

at 85 degrees your static pressure should be close to that. The system is empty, evac recharge to factory specifications, and get a good set of gages to check both pressures. I wouldn't try to top it off without knowing the high side..Could damage the system, and you..Hope this helps..

Email: Chick


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