AC Help!

[GRNCH]

Greetings!

I read the related posts from the archives and I still have some questions.

I had the system converted to R134a a couple of years ago on my '87 GN. What happens is that the clutch will momentarily enguage when the AC is first started when I do a cold start on the engine. The air blows cool for about 30 seconds, then just vent.

I bought one of those recharge kits and it came with a low-side pressure guage. It reads in the red at 110psi (I'm connecting it to the accumulator, where I would add refrigerant).

Looking at the diagrams from the good book, it shows a pressure switch, a A/C cutoff relay, and wires going to the A/C unit via 2 connectors. Now, I found what looks like a pressure switch (2 wires, female connector) on the side of the accumulator. Only it has a Lt. Grn wire and a Dk. Grn wire on it.

On another inline switch, there is a 3-wire connector. The colors are Dk. Grn, Dk. Grn/Yel, and Blk/Wht.

Ok, now that I'm totally confused, any suggestions?

Thanks in advance.

-Grinch

 

[Darkside]

This might help. Unplug harness to low pressure switch on accumulator. Take a paper clip and connect each end to the female connector in your harness(you are bypassing switch) start your car and see if ac blows cold. This should let you know if switch on accumulator is bad or not.

 

[FlyinGN]

This switch was bad on mine and did the same thing. My guess is that this is what is going on with yours too

 

[49-blues]

after you jump out the low pressurw switch,what does the low side pressure pull down to?should be 30-35 lbs-if not low on refrigerant.

 

[GRNCH]

Thanks Folks!

I'll try that as soon as I get home this evening (now, THERE'S a good reason to leave work early! )

I'll post the results.

-Grinch

 

[GRNCH]

WOHOOO!

It works!!

I did exactly as recommended. The switch was bad. The dealership had it within 2 hours for pickup.

Now, I'm real coooool!

Thanks to everyone!

-Grinch