1995 NA 2+0. The AC was blowing (cool, not ice cold) and abruptly shut off (blower and sounded like the compressor shut off as well). Suspected it might be low on Freon, and maybe the low pressure switch cut it off. Put the gauges on the ports, and it was low. Tried to add Freon but the compressor wouldn’t kick on to draw it in. Evacuated the system and was able to get it to take the required amount of Freon, and, when the compressor was running, the pressures were the spec the manual calls for. But the AC will still not stay on; it intermittently shuts off.

I checked the AC fuse; it was good. I understand that in addition to the low pressure switch, there is a system that cuts out the AC when the engine needs to shed some load, i.e full throttle (ECCI system?).

Any ideas where to start troubleshooting?

 

How long is it staying on? Is the AC getting so cold it is freezing up? Check the evaporator and see if it is frosting up. My 93NA uses a Throttle Suction Valve that will stop the AC if the temps go below freezing. It shuts off the compressor to stop a freeze up. The TSV is not used on the 95 model year but something else must do the same function to stop the compressor before a system freeze up. Maybe that device is shutting it off the compressor.

Also, the TSV on my 93 is no longer available and I have mine bypassed and running without it. So I have to be aware that if my AC begins to stop blowing cold, to shut it off for a few minutes to stop a freeze up. In the 3 months since I had the AC rebuilt with mostly new OEM parts (except the compressor which was rebuilt), I have not had a freeze up yet. And the AC blows real cold.

 

At this point, neither the compressor or the blower is coming on reliably. If you try turning it on in Econ mode, the blower would sometimes come on, and then pressing Auto would sometimes get the compressor to come on. When it does, the air is ice cold, and the high and low side pressures are just what the book says they should be at that ambient temp.

I purchased the Conzult software, and you can’t command the blower on with it. The one thing that stands out is the Air Mix Door 1 temp appears to be showing an open sensor (it shows -40 degrees when everything else is showing +80 degrees). But I’m not sure how that alone would cause the symptoms I have.