Just to be sure...

[swathdiver]

Truck was sitting for about a month without use, AC is now warm, system runs, no codes, Tech-2 shows high side pressure bouncing between 107 and 156, about 80 degrees outside.

Vent air is about 85 degrees, compressor is cycling on and off at idle. Did not leave the driveway. Actuators are fine, there's no cold air to be had.

Am I thinking right to discharge the system, put the vacuum pump on it for a few hours and then recharge the whole system through the manifolds, 3 pounds according to the sticker?

@91RS @Scottydoggs

 

[Scottydoggs]

with your tech 2 you should be able to see if the blend door actuator is working.

i dont enough about actual ac specs to be helpful on that part. but generally if the clutch is turning on and off it has refrigerant in it, if theres enough i just would not know.

 

[91RS]

What do you mean by bouncing? How quickly is it cycling?

 

[swathdiver]

with your tech 2 you should be able to see if the blend door actuator is working.

i dont enough about actual ac specs to be helpful on that part. but generally if the clutch is turning on and off it has refrigerant in it, if theres enough i just would not know.

Thanks Scott, yes, I can manually move the mode door with the Tech-2 and it is functioning normally.

 

[swathdiver]

What do you mean by bouncing? How quickly is it cycling?

Well, when I was sitting in the driver's seat looking at the Tech-2, it would oscillate pretty quickly between those values, every few seconds. A few minutes later I hopped out and had a look under the hood while she was running, the clutch was cycling on and off every few (4 to 5?) seconds. So having said that, I reckon both are in synch.

 

[Bill 1960]

It won’t need recharging unless it’s leaking, no? And if it IS leaking, charging is just a bandaid that won’t last.

I’d put my HVAC gauges on it to verify pressures hi and low side. Is the suction line from the evaps to the compressor cold?

 

[Doubeleive]

Let it run a little while then reach in and feel the lines, one should be cool and the other not so much, if that checks out then verify the door is working under the glove box by eye.
if both lines are warm then you have some other problem.

 

[swathdiver]

It won’t need recharging unless it’s leaking, no? And if it IS leaking, charging is just a bandaid that won’t last.

I’d put my HVAC gauges on it to verify pressures hi and low side. Is the suction line from the evaps to the compressor cold?

Didn't think to check the lines for coldness. Yes, I reckon that there is a small leak somewhere but being as I just got out of the hospital, not ready to do any big work on the truck. Just doing what I did was taxing enough today.

 

[Scottydoggs]

if the clutch is turning off and back on every 5 seconds you are low on refrigerant.

you'll need some real gauges hooked up to see whats going on. if its low, you also have a leak.

 

[91RS]

Well, when I was sitting in the driver's seat looking at the Tech-2, it would oscillate pretty quickly between those values, every few seconds. A few minutes later I hopped out and had a look under the hood while she was running, the clutch was cycling on and off every few (4 to 5?) seconds. So having said that, I reckon both are in synch.

If it is cycling that fast, it is most likely low on refrigerant. So add some dye and recharge it and find the leak.