AC killing all 92hp
 

Hey fella/fellettes,

Jus wanted to see if I was the only one who had problems with the ac. Whenever I push that little green button to put mine on, the car starts shaking real hard and the tachometer bobs up and down at about 700-300rpms, sometimes causing me to stall when I normally wouldn't.

Naira

I ahd the same problem.... just go to an ac place and tell them what its doing... and then tell them to check the fluids first... in my case I had too much and the AC would freeze up.... only cost me like $10

when hitting the a/c button my tach would often dip, especially if I had the lights on/ac going/radio playing/fog lights/amps and so forth.
You could try what the previous person said about the a/c refrigerant being low. That may be it, But I am not sure, my system was full and it still did it.
Bruce

I have never had the car stall when putting the AC on, though I rarely use it, but the idle does fluctuate. I'd say its because of the extra load suddenly put on the engine and the idle control valve might be slow to compensate for it. I can't really guess why it would stall though.

I would agree with here as well. I always use A/C, and eventhough I have no tachometer, I can hear my RPMs drop and the car shake for a second or two. Other then that, no problem, and definately no stalls.

The AC compressor definately places a greater load on the engine and the smaller the engine the greater the effective loss of power. When leaving from a dead stop this would require a slighty heavier application of the throttle. If you were to take off as normal the car could bog or even stall. Is this the situation you're talking about? If so, what you're experiencing is completely normal.

I used to have that problem, not sure what fixed it, as I did most of the changes in the winter, but my rpms used to dip bad when it was on, then I change the fuel filter and pcv valve, spark plugs, distrubiutor cap and rotor, fluids, and that's about as far as I can remember. Now the RPMs jump slightly when I turn the AC on(bump up about 50-100 RPMs for a sec and level out a idle speed). The thing is I'm not sure which thing improved what, all I know it's running a whole lot smoother now.

Your A/C compressor may be beginning to seize. The compressor shouldn't induce such a load to stall the engine, even at idle. Have you noticed any belt squealing recently with the A/C on?

Take it somewhere to have someone check it out.

first, assume a ac compressor sucks 25hp. second, mazda has a history of overfilling their ac systems with sometimes 100psi. ideally you want 60psi. drain some by sticking your key into the low end (drain) coolant socket (only so this with r134) and check the psi with a guage. you can pickup r134 system guages/filling hoses for ~$10. you compressor needs at least 40psi to kick on.

the reason for this is too much pressure will cause the compressor to run too hard/too often when it doesn't have too.

Yeah don't forget to hit yourhand with a hammer after you're done lowering the pressure just to see if it shatters. If not then you've probably just got severe frost bite. Its still illegal to vent R-134 to the atmosphere, at least in Ontario.

well first, do you have a auto, or manual tranny, i have a manual, and i know when i have my AC on its allitle harder to get the car moving smoothly, and almost stalling out. not randim stalling, just stalling because the lack of power. when i start out in first, i usually turn off the AC to make it easier on me. if this isnt whats happening to you, then just forget what i have said.

Yea mine doest the same thing and I have a manual. Most of the time if you leave the ac on and try to take a good take off you can forget. The car movies like you are trying to start out in second when you are in first. So most of the time I end up doing the same thing that (thegoldpro) does.

You guys need a bigger engine.

Now if I remember correctly...don't the 97 lx have the same engine as the 95-96???? I mean unless you did the engine swap I would think that you have the same size engine that I do.. But hey maybe I"m wrong!!!!

Yeah, I got the 1.8
Canadian model LX