It is 95 EX wagon, 4-cylinder Vtec enginewith high mileage. A/C did not give u "cold, cold" air for years, but still worked ok. Last week, I tried to add some R143a as adviced by a friend. But somehow, thestuff just could not get into my car. After I tried several times, something unusual came out. The engine works wellat idle(700rph) w/o turning on A/C. OnceIturnonthe A/C, every twosecond,I will first heard ofoneclick noise from driver side under the hood (at the same time, the rph go down to about 500). Then imediately, goback toregular 700rph. This whole processs repeat and reapeat.If you turn off the A/C, everythinggone.

Is there anyone know what is the problem orwhat could be possible problem?
BTW, the click noise sounds really like a switch or something. Short and clear.

Thanks a lot

 

I suspect you have overcharged AC system. When AC compressor engages, it overloads the engine and rpm sags badly.

You can't charge an AC w/o a manifold gauge set, except if you're very lucky and the problem happens to be a low charge w/ everything else fine. Your poor performance is probably for other reasons; cooling fans not engaging, condensor dirty or blocked, poor expansion valve performance, blocked receiver/drier, dirty evaporator, and other reasons.

See my post to another fellow w/ 94 EX wagon today.

good luck

 

I have a trigger/gauge that fits 134a cans. It was from a fairly large refill can, but the top is reusable. The gauge has pressures indicated as well as green/yellow/red ranges. I got it at Strauss Auto.

Inexperianced people should not use the high pressure port at all. You can get frostbite from the freon and most people are afraid of the blowoff when removing gauges, which can cause them to lose the entire charge while the gauges are half on.