95 3.1 Air Conditioning

[nato38]

Hello,

I'm new to the forum and this is my first post. I've searched through past forums and found quite a bit of information, but nothing quite as thorough or detailed as I might like.

Here's the situation:

I've had a 1995 grand am SE 3.1L v6 car without working air conditioning for 5ish years now, but recently I've decided I want to fix it, and fix it myself.

First, the serpentine belt turns well (as it should since everything else works well), but the a/c clutch does not engage (which was expected).

I attempted to charge the system (without testing for pressure first, since I would be entirely clueless as to how to do that). The result of this was a fairly noisy hiss which I could not locate at the time, and the compressor still not turning on.

The refridge that I added had a UV test dye in it, and so yesterday I attempted to find the leak. I believe that I located it at a joint where rubber hose comes into aluminum hosing near the High pressure service port, but I could be mistaken.

I was wondering a couple of things:

1. How do I pressure test the a/c high and low pressure sides?
(I know this seems like a stupid question, but I've never had it explained in such a way that I can understand it)
2. Does anyone have access to a diagram which details the a/c system in the 1995 Grand Am, 3.1L v6?
(I've looked for one of these for weeks but to no avail... I've acquired a bit of knowledge just by looking at the existing system and by looking at pictures of the individual parts. The only part which I'm not sure about exactly is the evaporator core, as far as I can tell I'd be walking down a hopeless path if I attempted to replace this on my own without quite a bit more equipment then I have.)
3. What should I expect if I pursue this project, what should my steps be.

Right now my planned steps are as follows.

1.) Properly look for leaks with a better UV light.
2.) Find any Leaks and attempt to fix them without replacing the hose assembly. (ie simply replace O-rings or attempt to Jimmy rig it).
3.) If necessary, replace the hose assembly (and expansion valve)
4.) If no leaks and sufficient pressure, check relays/sensors. (right now all electrical systems pass a visual inspection).
5. ) If necessary, replace compressor and accumlator/dryer (should I replace the accumlator/dryer when I replace the hose assembly anyways?)
6.) ... so help me god there better not be a 6.

Thanks, if you can answer any of my questions please respond.

[3100]

- test ERLS fuse (15A)
- test codes (if code 66 is set compressor clutch will not engage)
- low pressure side with engine off should measure in psi close to ambient temperature where you car is (example if in your garage temperature is 75F low side should be close to 75psi. Low side will have blue cap and it is accessible from the under the car. High side should be about 2.3-2.5 times higher than low side

I would disconnect compressor connector and jump the compressor with 12V to see if clutch will move in at all if not then clutch coil is bad.

also remember if pressures are too high or too low clutch will not work

[nato38]

Thanks for the reply,

The ERLS has already been tested and is functional, that was done weeks ago;

I believe that the compressor (or at the very least the compressor clutch) will need to be replaced, however both are entirely useless (except to act as a serpentine pulley) unless the system holds pressure; to my knowledge it does not.

To be clear, the compressor does not engage, whether or not it will is another issue entirely. I'll see about testing codes.

What I need at this point is a quality diagram of the system;

I know where the condensor is (obviously), I know where the compressor is,
I know where the receiver/drier/accumulator is. At some point however theres too much junk in the way for me to find the expansion valve and the evaporator.

At this point I think my plan is as follows;
0. Leak and pressure test the system;
1. Remove compressor, accumulator, expansion valve.
2. Flush the system of any contaminants.
3. Replace with new parts; possibly replace or reuse sensors, I'm not decided.
4. Re-charge leak/pressure test
(Can I do step 4 without hooking the system up to a vacuum pump first?
5.Bring system to a mechanic to have it properly charged (if step 4 is successful)
6. (if step 4 fails) Find leak and replace necessary component (hopefully just hose assembly)
7. Re-charge/leak/pressure test.
8. Repeat (5).

Do these steps make sense? Am I missing anything? Am I hopelessly over my head?

[3100]

evaporator and expansion valve is under the dashboard where your heater core is.

[nato38]

Thanks; that might be enough for me to get what I'm looking for.

If I can figure out how to access the heater core, the steps will be very similar, then, to access the evap core/exp. valve?

I'm working on a limited budget, and the repair info on autozones website simply tells me that it's dangerous to work on a/c systems, and doesn't tell me anything about the stupid system.