a/c problem, 3sge swap a/c Options

[99gt3sge]

well before i swapped my 3s my a/c was working nice but the compressor was making noise, so naturally when i swapped i used the jdm compressor and ever since then i charged the system and now only works when the car is cold or when i'm on the highway. on stop and go it stops working have any of you guys experience this? the only thing I'm guessing that the compressor that i'm using might be for r12 and my car uses 134 since it's a 99.

[Smaay]

that has nothing to do with it.

your compressor is kicking off because something in your wiring is sending a signal to turn off the compressor. doublecheck your wiring.

Or it could be a funky compressor.

but im 100% sure it has nothing to do with R12 or R134

[VavAlephVav]

I'm going to say that if the compressor on the 3s was working in the first place it doesn't necessarily matter if it was for r12 or not. at least for a while it should work fine, the pressures the system operates at are close to the same but the different kind of oil used in R134a will eventually ruin it.
for that matter when you charged it did you put any oil in? it circulates throughout the system with the refrigerant and only a little of it stays in the compressor.
otherwise can you tell if the compressor is cycling on and off repeatedly? if you get out of the car and watch it you would hear the click and see the clutch on the compressor stop and go. like when it's low on refrigerant there is a low-pressure cut out switch(connector on pipe near firewall) that will stop the compressor from running below a certain point.
up in the front near the bottom of the radiator (battery side) is the liquid filter/dryer, it has a sight-glass window so you can see what the refrigerant is doing. if you look and see a solid stream of liquid you are good, if its low or there is a blockage you will see bubbles in the refrigerant.
Also did You charge it or did you have somebody else do it? Did you pull a vacuum on the system before charging the refrigerant and oil? do you have a manifold to see the pressure on both sides of the system?
The pressure doesn't matter really except that we use it to know the Temperature of the coils. The low side(blue) gage should be around 35psi which is 40 degrees, and the red gage should be at a temperature that is about 30 degrees hotter than it is outside. like on a 90 degree day it would be 120 degrees which is 171 psi for r134a, although it often may be higher than that if you're sitting still.
on recirculate the temperature of the air coming out of the vents inside should be not higher than 55 degrees.

This post has been edited by VavAlephVav: Aug 27, 2014 - 7:21 PM

[Smaay]

I'm going to say that if the compressor on the 3s was working in the first place it doesn't necessarily matter if it was for r12 or not. at least for a while it should work fine, the pressures the system operates at are close to the same but the different kind of oil used in R134a will eventually ruin it.

thats not true. my 4 runner came with R12, all I had to do was get the adapter fittings and charge it with r134. been working fine. did the same in my All-Trac. worked fine for years.

[VavAlephVav]

I agree it should work for quite a while, its just not ideal. I've seen a lot of things work even though they told us it wouldn't in school.

The deal is that the new oil, poe or pag, act as a solvent and if there are carbon deposits in the condenser the oil will knock all that stuff loose and then it would plug up your orifice tube.(metering device)
Its more of a problem if the system was really old and dirty.


Either way if you're saying that it kinda works up on the highway but not so much when idling i'd guess you have either not enough refrigerant or it wasn't charged well.

This is my thread on a proper evacuation and recharge, if you don't do it just right it won't be as cold as it should
http://www.6gc.net/forums/index.php?showtopic=92850

This post has been edited by VavAlephVav: Aug 28, 2014 - 11:26 AM

[mi645]

check the resistor, and check expansion valve, that happened to mine after the swap. but i barely used my ac b4 swap im still using 5s compressor, i didnt wanna use 3s compressor because i believed it uses a different resistor or something. thats y i just stuck with the oem 5s comp. i have a spare 5s compressor if u wanna try it Neal

[99gt3sge]

thanks for the responses, @Mi645 which resistor are you referring too? the one for the blower? also ill check the a/c with the gauges and see what psi its reading. its funny because on my swap i used the jdm harness and on my buddy's ride i use the 5s harness and his a/c works like a champ but i left his original compressor and i never discharged it. i will do these checks and ill let you guys knows what happens thanks again.

[Bitter]

System sounds over charged or contaminated with air, get it pulled to a vacuum then recharge by weight not just pressure. In other words, take it to a shop with an AC machine.

[mi645]

yeah he has an AC machine, he owns a shop.

[Bitter]

Good, so get it pulled to a complete vacuum, let it sit at vacuum for a while, then charge it to the proper weight, and run the engine till it's hot and hold a fast idle at 2500 rpm and see what's going wrong. It could even be that the AC fan isn't cycling on! That will be easy to see happening, you can verify it's a heat over pressure by spraying the condenser down with a garden hose and noting the drop in high side pressure and the increase in cooling in the car.

[Syaoran]

I'm having a similar problem. Upon first start, it will work fine and stay working no matter what. However if I turn it off at any point and turn it on again, it will not stay on.

I have to give it a while before it starts working again.

[VavAlephVav]

that's really odd, it may be somekind of a control problem. If you can get a refrigerant manifold and hook up the gages and report what the pressures are doing.

[Syaoran]

that's really odd, it may be somekind of a control problem. If you can get a refrigerant manifold and hook up the gages and report what the pressures are doing.

In my case, the gauges read fine.

When I turn it back on, it's as if the compressor never kicked on, but it does because the RPMs drop. The low side pressure stays at around 100 psi when the compressor apparently doesn't kick on.

When it works fine, the pressures are at around 30-35 psi which is perfect.

[VavAlephVav]

hmmm then you've got maybe a problem in the low pressure cut-out switch (connector on pipe near firewall), or you've got some problem with the switch on your AC control, or the connector on the compressor I'd guess.
when the compressor is off the high and low side will equalize and read about the same so that's normal.