Hey guys,

I have a 94 I bought in 98 with A/C fully intact and working, however it didn't work 5 or 6 years ago and I've been planning to remove it for ages. Lately though, I've been reconsidering and thought it would be worth a try to get it working. These days, I'm not so concerned about performance and saving 30 pounds, as much as I'm concerned about making the car practical so I'll start driving it more often. Working A/C would be a huge step.

I see a lot of people on this forum mention re-installing A/C by just adding all the parts back and recharging the system. Since my parts are there, should I just start by getting R134 from an auto parts store, filling my system, and then just see what happens?

I have a Power FC (got this AFTER the A/C stopped working). I remember there being a lot of people whose A/C didn't work with the Power FC. Was a real fix for this ever discovered? I'd hate to go through all the trouble just to find out the AC will never work with my Power FC.

Last, even pre-PFC, when I'd try to turn on the A/C, the red A/C light wouldn't even turn on. Is this what's supposed to happen if there isn't enough refrigerant... or does this indicate another problem (such as a wiring issue??) Last time I asked, everyone told me the light should come on and blow warm, even if I'm out of refrigerant.

All help is appreciated. If someone is very experienced and could help me with some steps to troubleshoot the root of the problem, that would be very considerate and very appreciated.

Thanks,
Wade

 

Hey Wade,

Good to see you are still around. Here's some info of the PFC A/C fix(es):

https://www.rx7club.com/power-fc-forum-47/my-luck-c-fix-just-my-2cents-383751/

The light on the A/C should turn on even if you are low on refrigerant. Unfortunately, I haven't needed to troubleshoot any A/C problems myself yet to provide any more help. I'm sure someone with a lot more knowledge on the subject will jump in. Good luck.

 

the system is a closed system meaning if youve lost a charge then theres a leak somewhere. You normaly would want to replace the reciever drier (dessicant isnide) but you might be able to get away with what you have if it hasnt been exposed to too much moisture.

your also going to have to get it charged and properly tested for leak check and operation

I just finished an auto a/c class at school and have been breathing it everyday for the last month. Id be glad to help with any more questions you might have.

 

As already stated you need to replace the receiver/dryer. The system needs to be evacuated before you charge it, to remove the air and moisture in the system. When you recharge, put some dye in also, so it will show you if you have any leaks.

 

Thanks for all the help so far.

Is it *necessary* to get a new dryer? (Is that the cylindrical part near the battery?) My car has been garaged for the past 8 years, so is it possible the part is still good? What goes bad with it? What kind of ballpark cost am I looking at to get the dryer and the system charged?

I'm not even sure the system needs charged. Like I said, the A/C light doesn't even come on. Could easily be a wiring problem.

I still have the stock ECU so I could use it temporarily to eliminate the PFC as an issue. But the system didn't work before the PFC so I know there is something else going on.

I really need some direction. I don't really want to get the system charged until necessary, unless it's dirt cheap.

Can I get it charged with dye, then force the compressor to run, to see if the system at least mostly works, and to prove the problem is wiring or a problem with the switch itself?

Thanks,
Wade

 

No, it is not absolutely necessary to replace the dryer. The dryer removes moisture from the system, but can't hold very much. So IF your system is open to the atmosphere a dryer would be a good idea. I have no idea how much a dryer goes for, but around here a charge is about $125.

If your light doesn't light up I would start with making sure the electrical side of the a/c is working properly. The fsm will walk you through testing.

 

Also, don't switch to R134. My A/C guy says it just won't cool sufficiently in the RX7. Don't worry about the PFC, if it doesn't work on a couple of the fan speeds (once everything else is fixed), there is a good fix for that here on the forum.

 

That's a good point, after reading some of that PFC A/C thread, I realized it only affected certain fan speeds. I'd be happy if even a couple of the fan speeds worked.

Since the A/C light doesn't come on, I like the suggestion of starting there. It's possible I still have refrigerant. I'll dig in the manual a bit and see if I can find some things to check. I've had my dash and climate control parts out more than once, and also removed a lot of wiring associated with the airbags and possibly some other things, so I think it's very possible something is missing or disconnected.

Can I just jumper a relay under the hood to see if the compressor kicks on and if the air blows cold or not?

Thanks,
Wade

 

Yes, you can jump the relay and see if the comp. kicks in.

 

I think (though am not 100% sure) that the AC light should come on irrespective of the state of the AC system (assuming that the fan switch is in position 1 or higher - try 4 if you have a PFC because 1 does not work on some cars).

The Body Electric Troubleshooting Manual has a set of really good AC diagnostic procedures in section G.

 

I always thought it was supposed to light up too even if the AC was out of charge. So I may have a wiring issue.

It's too cold now and my car isn't running at the moment anyway. Thanks for the help, but I'll have to revive this thread next spring.

Thanks,
Wade

 

you will also need to check if you have damages on your AC lines, i removed the whole lines and found the source of the leak by the radiator, some of the guys i know had the same spot where the AC piping was rubbing through the chasis frame.

 

dont forget about the o-rings for all the lines, they tend to leak from there as well due to age.

 

Check the fuse. And FYI, if you are having trouble with fuses blowing, check your air pump, if you still have one.

 

Wade, you'll want to check out this thread.

 

Thanks for the tips, guys. I am pretty sure that I have a leak somewhere after having to bend the lines a bunch to get aftermarket parts to fit. :/ But first I need to get the light to come on in the dash, as I think the AC isn't even trying to come on. Then I can move on to finding leaks, recharging, etc.

Thanks,
Wade