I took all the advice from this fourm and took apart the dash and found 2 diaphrams one closer to the firewall and one closer to where your knee would be if you were driving. The one by your knee is broken away from the black box it attached to.

Is there anyway to fix this? Is this the one that controls the recirc vent or something else?

The issue I am having is cold air at start up and low speeds but as soon as you get on the gas a little the air stops blowing and then doesn't get cold again.

thanks in advance
-Ian

 

To see if it is the recirc one or the one you think it is remove the hose and plug it.
Then take for a test drive and see if it goes back to normal. If not then it is another one or a Combo of 2 of them.

 

At idle in the driveway, I took off the vacuum hose on the bad one and there was no sucking, I took off the (good) other one and there was great suction. Does this mean anything?

what is the best way to plug the vacuum line?

-Ian

 

That does not mean anything because the one you took the hose off of that had no vacuum might not be turned on.

Find something to fit on the hole of the hose tight and that should be fine.

 

ok after a test drive the air is still blowing but not cold once I get on the gas.

I tested the the freon with one of those kits from walmart and it showed the pressure was good... in the green anyway doesn't give a number.

Any suggestions what I should do next?

I was thinking of trying to jb weld the diaphram that is broken off the box back into place???

Are there any diagrams anywhere that show the system in detail and what they do?

 

I will have to try to find a diagram.
Did you block off the recirc hose?

 

fixed it...

My big misunderstanding was when the gage showed 100psi... I thought that was overpressure due to a blockage or something and that the compressor was cycling off because of this high pressure build up.

What I failed to understand is static pressure and that at 90 degres F the static pressure of 134a is about 104 psi Here is a link explaining that.

Basically when I was driving and I stepped on the gas the pressure in the system would drop about 20psi causing the compressor to cycle off. Normally it should kick back on at 45 psi. Mine didn't I watched the gage clime to 100 psi. I thought I had a blockage or something was causing high pressure build up and causing the compressor to cycle off. In the end the clutch was warmed up and wasn't engaging after it cycled off due to the low pressure switch.

I was able to pull the clutch face off with it still on the car. I took some channel locks and squeezed the face into the clutch so that I could undo the center 10mm bolt. I then took 3 screwdrivers pried one on top and got under the car with the other two and pried against the one on top and it poped off nicely. I took it out and 2 washers were inside. I left the thicker one out and put it all back together.

Now it runs like a champ and doesn't stop.

An easy way to see if this is your problem, get a cheap gage from walmart and a can of 134a. Hook it up to your port by the accumalator and start the car. You should hear the compressor kick on and watch the gage it should be somewhere in the green. If not add 134a until it is. Now let your car run for a few minutes to get good and warm. Now take the pressure switch off of the accumalator and the compressor should stop and you should see the gage climb into the red. Plug it back in and if yours is like mine the compressor will not kick back on and it will stay in the red. If so you need to shim the clutch.

Here is a decent link on shimming

Here is a good link for general info

Here is another good link for the s90

 

Glad you got it fixed.