OK, post #5 directs you to connect to the tubing line towards the front of the car, remove the black cover, quick connect there. That is the low side downstream of the orfice.

 

Sorry keyinkpk, everything else indicates that port which is closer to the front of the vehicle is the high pressure side (it's the smaller line from the compressor, and the recharge kit doesn't fit on that port). If I have to plug into that port I'll have to go tracking down some kind of an adapter that doesn't come with the recharge kit which also makes me doubt that's the low side. Do you have some drawing or a page from the repair manual you can send?

 

Glad you know more about it. Next time you can post a reply as such, and not ask for information

 

You should charge on the low side. I assumed that you haven't added any gas which why I thought your ready was a little high for the low side.

What do the instructions on the can and packaging tell you to do?

The hi and lo ports are a different size for a reason. That's so one doesn't hook the gauges up wrong. The aftermarket kits that I'm familiar with hook to the lo side only.

It's a lot easier to diagnose w/ a gauge set.

 

Thanks 73shark, I agree I should already be connected to the low side since that's the only port the charge kit fits. No I haven't added anything to the system yet (haven't pierced the can that came with the refill kit). Instructions on the can say to 1. Connect the can to the hose, 2. connect the hose to the low side, 3. Turn on the AC 4. When the compressor is on pierce the can 5. allow contents of can to enter vehicle AC until pressure gauge is in the green zone.

The thing is the pressure is already above the green zone, which could be ok since the 134a that's already in the truck is supposed to run at a higher pressure then the 12a that's in the recharge kit. To me it seems my system is probably not leaking and already has a full charge.

What else can I check to see why the compressor is cutting in and out?
Thanks!

 

What does the pressure do as the compressor cycles? IOW what's the pressure w/ the compressor on and when off?

 

If it is over full, it could be tripping the overpressure switch. As stated you really need to look at both sides of the compressor. The downstream or discharge pressure will vary with rpm. If it has too much it also will not cool.

 

Kind of like Goldilocks, it's gotta be just right.

 

Just got a chance to do this after returning from a long camping trip with no A/C...I reconnected the gauge (to the only port on which it will fit), started truck, turned on the AC, and the compressor no longer engages at all!! The pressure's also a little lower at about 45psi as opposed to 55psi before (engine and atmosphere is a little colder now which may be affecting it?) . Both readings are still above what was noted on the refill kit as a full system (for 12a coolant at least, I have no idea what the original pressure should be, any idea?).

I see a connector way down on the compressor. I was thinking if I could check the voltage on the connector with the AC on and off I should see 12V when the AC is on? This might help troubleshoot the electric clutch? If I don't see the 12V with AC on or off, then check something else?

Do you know an easy way to check the voltage at the compressor clutch? Take the wheel well out maybe?

Thanks!

 

Are you saying R12? If you put R12 in it, you just toasted the system. Pull the connector off the clutch, stick a voltmeter in to.