Another A/C problem

[Y2KpewterZ]

I tried the A/C for the first time a few days ago since I got this thing. It blew cool, but not cold. A simple recharge was in order. I charged it untill it read good on the gauge that comes with the refrigerant cans (in the "green", inbetween the V @ about 45-48psi on a 90* day) anyways it blew nice and cold on my 30 minute ride home but the last five minutes it started to blow only "cool." I checked the pressure when i got home thinking that maybe it leaked out, but no. Still right around the same psi. Any ideas?

 

[SunlitComet]

first, was the pressure you were reading while the compressor was engaged? second, exactly what did you use to recharge it. third, pic of product please.

 

[Y2KpewterZ]

Yes, compressor was running when pressure was checked. I used a large can of, iirc interdynamics standard r134a with stop leak additive or some crap. It was one of the cheaper bottles on the shelf. I noticed it being cold, then going to not so cold yesterday (it was out of the V range and at the lowest of the green area on the gauge) so I topped it off today with 12oz of this today


I also noticed after the air begins to get warmer I will turn the ac off. Leave the truck running then 5 minutes later cut the a/c back on and it will begin to blow cold again.

 

[SunlitComet]

how are the temperatures on each line on the compressor?

so did adding the refrigerant help or worsen?

---------- Post added at 02:16 PM ---------- Previous post was at 02:15 PM ----------

kinda sounds like the orifice tube is clogging maybe.

 

[Y2KpewterZ]

Edit: i found my receipt from yesterday and this is originally what i added..

I dont have anything that can measure temps on the lines? Unless I should just go by touch?

The refrigerant definitely helped. When is blows cold, its alot colder then before I added any.

Ive researched the orifice tube a little bit, and from my understanding its a piece inside one of the A/C lines, located near the firewall. (Yes, i have rear a/c).

Im not too familiar with the workings of a/c units and such. Is this a "professional" job or can i tackle this myself?

 

[SunlitComet]

ahh rear a/c now we are getting somewhere. do you have the same problem in the rear as you do in the front?

 

[Y2KpewterZ]

Yes.

 

[SunlitComet]

well then both metering devices are screwed or the charge is not correct or the compressor is malfunctioning. i strongly suggest you get a performance test done. this involves pressures on both high and low lines with simultaneously temp and humidity of outside in front of grill and same for measurement inside with upper vents only and measuring instrument in the center outlet. fan on high. all done about 5 min after turned on. from this info is is much easier to find the cause based on the numbers and the way the gauges move around in the process.

 

[Y2KpewterZ]

Well back to the shop it goes for a performance test

 

[Matt06Yukon]

Yes you can do more damage overfilling it. Get a good set of gauges if you wanna continue playing with it. You know as soon as the compressor starts cycling off and on that your low on refrigerant.