Weird A/C problem, Civic 97 EX/AT
 

Hi everyone, my first post here, nice forum :)
I have a problem and I hope someone will help me with it. My air conditionning unit (AC) doesn't cool the air. Here's what I've done (all day today):
Tested all the AC-related relays and fuses (under dash and under hood). The red wire going to the temp control sensor from the relay is fine and there's 14 volts on the Field Coil (right after the Temp sensor) when the car is running and the AC switch in ON.
The air is still warm and the heat exchanger (under the glove box) doesn't get cold. The blower fan (under glove box) is spinning fine. The fan on the heat-exchanger (outside, on the right of the radiator) is turning too.
Got 2 cans of R134a-compatible gas and filled the system, same problem.
When the AC is turned on, the RPMs go higher (from about 700 to about 1200) and go to idle slowly. When it is turned off, the RPMs go high again (to about 1000), then drop to 700 slowly.
If I take two long wires from the relay that activates the compressor and put my ear just above the compressor (car is running at this time), and I short them, I don't hear any clicking sounds (as suggested by the service manual). I wonder which part should click and what happens when it clicks.
Since I got this car (2 years ago), the AC never worked.
I also have the Haynes manual and the original Honda manual. Tried everything there, no help.
Car is a Civic 97 EX automatic, 4-door.
Open for suggestions and experimenting :D
Thank you all for answers.

[Deleted]
 

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RE: Weird A/C problem, Civic 97 EX/AT
 

I wonder how I didn't think about it before... :D

Seriously though, I fixed the problem by connecting the solenoid on compressor to the battery directly many times, quickly. This probably unblocked the rust. It worked for one day and doesn't work anymore. Somehow, it's having a hard time to pull the compressor's pulley to the compressor. I'll have to take it apart somehow, without letting the R134a out...wish me luck :D

RE: Weird A/C problem, Civic 97 EX/AT
 

im not sure y the rpms are increasing when u turn the ac on but the reason that its not working it could be a leak in ur system or the condensor or compressor is bad....there are some suggestions hope all is good soon
seth

RE: Weird A/C problem, Civic 97 EX/AT
 

Thnx Seth.

No, actually the problem is that the pulley on the compressor is probably rusty, because it doesn't get attracted to the compressor's clutch. Now I know how it is supposed to be and how it is. I'll have to take that whole thing apart and clean it (making sure that freon isn't coming out during the process).

RPMs increase because there's a bigger load on the engine (the ECM "thinks" that the compressor is turned on, so it makes the engine spin faster to avoid stalling).