A/C problems don’t know what’s wrong

Yeah, it was only 104°F today and only 92° now at 10:40pm.

That's just because sitting outside the interior heats up then the AC can't keep up with the heat from the sun pouring in. It still means the AC is weak for some reason. Could be a bad fan not pulling air through the condenser, could be a clogged condenser (on the fins), could be a clog in the freon line near the evaporator core, could be the evaporator core fins are clogged.

Does the compressor stay on constantly or does it cycle on and off even when the air at the vents is hot?

If you take the blower motor out you can reach a camera up and take pictures of the evaporator core to check if the fins are clogged.

And I assume you have it on recirculate to help the ari cool off better?

Maybe find a good AC mechanic that can assess the AC system and figure out what's wrong without throwing parts at it.

 

Yeah I checked the compressor today it was on whenever the a/c was on and didn’t switch off. I have recirc on too, maybe I’ll try to take the blower out and check the evaporator. How would I tell if it’s bad? If it just looks gunked up so no air can get through the fins?

 

Accumulator = Receiver/Drier and yes they do. Google search image below of location.

 

Dah my bad. I was thinking accumulator like the old chevys had on the low side line.

 

Ah I see your though process. All good man.

 

This ^

Rutro..........

You betcha. These things aren't that complicated.

Agreed.

I'll toss out my internet guess. At this point that's about all anyone can do.

You'll have lousy pressure readings that will indicate a failed or failing expansion valve.

The key is you do need an honest mechanic who is skilled in AC work.

 

Late to the party.

I've had a similar issue on my wife's 3rd Gen T4R, and wound up replacing the expansion valve and the evap. core. Both nasty as hell.

On my Taco, I have a different issue....My A/C would blow nice and cold for anywhere from 15 min. to 2 hours, then get hot. I could let it sit for a day and it would blow cold again. Just got back from a shop I trust and lets me hang around while they do the work, and when they first hooked to it, A.) I had a bad valve, B.) I was low on 134, but C.) I had a vacuum on the low pressure side (can't get any lower pressure than that) and about 130-150 psi on the high.

Now, I know that I've seen "fluid" in the sight glass of the condenser, but it was more white than green. But they left the system empty for me to be able to fix it....suggesting that the lines might be clogged. They also suggested that I might be able to throw some compressed air into the system and blow the clog out...I don't know.

Looking for suggestions, cause I'm a fat arse at 350 lbs. and this 90+ temp sucks.

 

A closed, not opening or frozen (moisture contamination freezing in or around expansion valve) will do that along with the compressor pulling a vacuum against the closure.
One would think an obstruction would be more constant.

 

My advice, take it to a pro. I have worked on AC before and it can be a bear even for an experienced mechanic. If you don’t have a set of gauges, you’re pushing a rope trying to diagnose the issue.

If you have a set of gauges, it isn’t a super complex system. When the compressor is engaged, it creates a pressure differential. The “low side” is downstream of the condenser (basically a radiator inside your cabin, heat exchanger) and the high side is between the compressor and expansion valve. Each side has a range of operating pressures, any any discrepancy indicates a problem.

But without gauges, you’re just guessing.

 

Just to give an update on my situation.

I did as the shop suggested. They evacuated the system, and I brought it home. I opened the 2 lines going through the fire wall, and tried to blow compressed air through them. No luck. I tried the rest of the system, and there was minor restriction to air flow. I went ahead and ordered the expansion valve and the evap. core. I had the system swapped in about 45 minutes. Took it back down to the shop for them to do a leak check and re-charge the system. Total investment was $100, $60 in parts, and $40 for the shop.

 

I may be wrong but I don't think you should be able to blow compressed air through. The expansion valve separates the high and low sides with a pressure differential of 200psi give or take. The expansion valve meters a tiny amount of liquid freon through which turns to gas at a lower temperature. There may have been a restriction, I'm just not sure the compressed air test was sufficient to be 100% sure that was the problem.
Anyway, glad you got it working.