air conditioner doesn't work - not cold and compressor is not on

[tominos]

so it's a 95 atx sho, bought the car like this.

with the engine on, the low side reads 110psi and the high side also reads 110psi. isn't the low side supposed to be lower? around 40psi or so?

with max ac on, the ac compressor does not spin, i tried putting r134a into the low side, but it doesn't go. help me out here guys.

what should i check first?

 

[naval-avi8or]

so it's a 95 atx sho, bought the car like this.

with the engine on, the low side reads 110psi and the high side also reads 110psi. isn't the low side supposed to be lower? around 40psi or so?

with max ac on, the ac compressor does not spin, i tried putting r134a into the low side, but it doesn't go. help me out here guys.

what should i check first?

Clutch airgap to large due to clutch wear. Re-gap or replace clutch. You can also verify that you have voltage at the clutch when commanded on. If so it is as stated above if not disconnect the press/cycling switch and use a paper clip to short the two prongs on the connector to engage the compressor clutch. If this works than you cycling switch is bad.

 

[tominos]

how should i get at the compressor, from the top or bottom?

 

[SASHO91]

What is the reading with the car off???

it should not be too much more than ambiant temp.

just FYI.
the low side should be operating at 25-45psi. and the high side is going to be 100+ the ambiant temp.

It sounds like the system is overcharged.

you need to take it into a shop that does ac work... have them remove the frion and evacuate the system. then they should put in the correct amount.

 

[tominos]

so i started looking at the compressor with the battery and battery tray out. the plug on the front of the compressor is not connected, i tried to connect it but it doesn't seem to want to go in the plug, since it is facing the front of the car, its hard for me to see whats going on inside there. the plug maybe goes in 2-3 mm and no more, maybe the prongs inside are bent on the compressor? the latch on the plug is broken too which maybe why it was disconnected.

can it be that the low side is at 100psi? meaning can it be charged that high?

 

[SASHO91]

that plug shouldnt move too much.. what you stated is about right.
but i would try and get a small mechanics mirror to check the prongs out. just to be sure.

when your charging the system, the pressure should not be that high...

thats indicating that the ambiant temp is 100+ ....

I think what happend is that the PO took it to a rinky **** ac mechanic... they thought it was low on frion.. so they put more in... then they took it back and said its still not working so they put more in... thus creating an overcharged system, all because the compressor wasnt hooked up...

like i said.. dont try to mess with it...
Take it to a reputable ac shop, and have them diagnois it better.... without being there i cant really give you a clear cut answer... not unless you go into some more detail...

see if you cant get the compressor to kick on...

 

[tominos]

what does po mean?

i have ac again had to have the window down today while on the freeway.. sucked.

so it was the plug after all, i couldn't see the prongs and didn't have a mechanics mirror handy so i just used a right angle small pick and bent the prongs up and down till the plug fit again and voila.

thanks for all the help guys, now just gotta do the fuel pump replacement, 96 brake upgrade for my warped rotors, 2 o2 sensors, upper and front 60k.... the list goes on, lol.

 

[tominos]

oh the readings were spot on with the compressor running. ac on, engine on, high side read about 150-160, low side read about 30.

 

[SASHO91]

PO.
previous owner.

sounds like its all good...

may be alittle overcharged, but thats not too big of a problem... as it doesnt seem that overcharged...

 

[etc1006]

At least you have a car w/134... Mine has 12, and the system is low... I can just barely hear a hiss when I check the schrader valve... I have 1 can of 12, but not tap for it, lost ot somewhere. I do have a 134 conversion kit from my old PGT. And the vac pump and gauges... I just don't know what exactly I want to get in to.

 

[tominos]

i've done a conversion on a 91 sentra before from r12 to r134a, was so easy..

its just draining all the old stuff out(which you want to do at a shop) but since mine was already empty, had a leak which didn't go away, lol, then just unscrewing the old fittings and putting on the new fittings.

used a conversion kit from an auto store.

 

[SASHO91]

One thing you need to know...

you cannot use pag or mineral oil in a converted system... IIRC its ester oil...

 

[tominos]

yeah, i used the bottles that came with the conversion kit with ester oil.