A/C won't blow cold

[Mazdaspeed96743]

Okay after pushing the AC button on it lights up, Then after pushing the switch to the 1,2,3, and 4 position I feel air comming from the vents meaning the blower works fine but it just won't blow cold air, heater works fine though what could be wrong? Do I need to replace my a/c compressor or can I just refill the refridgerant? not too sure what to do or check.

[solo_ryder]

Sounds like you need a recharge sir

[eyezpinned]

i agree w/ solo... had to retrofit/refill my ac last summer... pretty straight-forward.

before you start: check if compressor is kicking on. if the refrigerant is too low the compressor wont come on. basically if you hit the ac button and the car doesnt bog down/ no clicking from the compressor, your refrigerant is low...

1. locate your low port ac line. it'll be on an aluminum line usually w/ a black cap and looks like a tire valve(mine's passenger side near firewall)
2. check if you need to retrofit (youll be able to tell because the r134 coupler isnt compatible with an r12 valve because an r12 valve is thin like a tire valve r134 is thick).
3. purge the system if you have the old setup (get it done professionally if your an eco-friendly type) have to do this dont mix r12 and r134
4. swap out the old valve with a valve puller thing. screw in the new r134 valve.
5. turn you ac on full blast fill with new r134 (make sure you take into account outside temp 80 degrees fills to 50 psi, 90 degrees 60... no lower than 50 no higher than 60 though important because too low of a fill gives you that ac that's never quite cool enough. the compressor should kick on and off as you fill, and psi goes up and down. you want the psi reading to be within range WHILE COMPRESSOR IS ON. check the air. if cool, you're cool

PROBLEMS: if after refill car goes warm after a few days, you have a leak. start by making sure system is empty and then replace the the o-rings (follow each ac line until you reach a bolt to another stretch of line). unbolt each piece and replace the little o-ring. now refill the system again. follow your aluminum ac line to where it meets a black rubber line. after refilling WITH CAR OFF manipulate this hose. if you have a line leak hissing will become apparent when doing this. pinpoint the hissing with soapy water if not obvious and replace defective part.

i also advise getting the cheapest possible r134 until you identify all leaks. because if you run into a leak, you may be refilling a few times

[69shelby]

hers what i did, after you check the pressure:
1. check to make sure the compressor is working, put 12v to the wire off the compressor and when the engine is running, see if the clutch engages, if it engages the compressor and clutch work.
2. make sure the fuse is good in the eng compartment and turn on the switch and see if the relay clicks, if not, jump the 2 wires to make it run the compressor, if this runs the relay is probably bad. , if it runs jump the 2 wires one the low pressure switch to see if it runs, if not the pressure is low or the switch is bad.
mine was a 4cyl so the set-up is a little different. now if only i get off my butt and find my leak...

[DimaK]

i gotta do this to my pgt..........one of the major reasons i bought the thign it was because of air, now it quit, son of a....

[ninjajim4]

bad, expensive advice.

you need to get your system emptied not only of R12, but also the oil that matches it. R134 uses a differnt type. you also NEED to have your system evacuated before filling it, and it's at that point that you check for leak. your system should be able to hold a vac overnight. if it doesn't, it's leaking. you should NOT be wasting freon to see if it's leaking unless you're dye injecting the system and want to pinpoint the exact place.

i agree w/ solo... had to retrofit/refill my ac last summer... pretty straight-forward.

before you start: check if compressor is kicking on. if the refrigerant is too low the compressor wont come on. basically if you hit the ac button and the car doesnt bog down/ no clicking from the compressor, your refrigerant is low...

1. locate your low port ac line. it'll be on an aluminum line usually w/ a black cap and looks like a tire valve(mine's passenger side near firewall)
2. check if you need to retrofit (youll be able to tell because the r134 coupler isnt compatible with an r12 valve because an r12 valve is thin like a tire valve r134 is thick).
3. purge the system if you have the old setup (get it done professionally if your an eco-friendly type) have to do this dont mix r12 and r134
4. swap out the old valve with a valve puller thing. screw in the new r134 valve.
5. turn you ac on full blast fill with new r134 (make sure you take into account outside temp 80 degrees fills to 50 psi, 90 degrees 60... no lower than 50 no higher than 60 though important because too low of a fill gives you that ac that's never quite cool enough. the compressor should kick on and off as you fill, and psi goes up and down. you want the psi reading to be within range WHILE COMPRESSOR IS ON. check the air. if cool, you're cool

PROBLEMS: if after refill car goes warm after a few days, you have a leak. start by making sure system is empty and then replace the the o-rings (follow each ac line until you reach a bolt to another stretch of line). unbolt each piece and replace the little o-ring. now refill the system again. follow your aluminum ac line to where it meets a black rubber line. after refilling WITH CAR OFF manipulate this hose. if you have a line leak hissing will become apparent when doing this. pinpoint the hissing with soapy water if not obvious and replace defective part.

i also advise getting the cheapest possible r134 until you identify all leaks. because if you run into a leak, you may be refilling a few times

[Mazdaspeed96743]

Thanks alot guys.. I am a complete newbie when it comes to these things.

[Mazdaspeed96743]

Update: Okay I just talked to the guy who sold me the car and he said there is a leak somewhere. He refilled the ac and a week later it did not blow ice cold air like it should. Now to find the leak.. Could it be just a hose replacement to do the trick?

[eyezpinned]

i had a small leak in the rubber hose that hangs under the radiator (in my 4 cyl). like i said when the system's full you can sometime's hear the leak (as which happened with mine). i mean you can buy dye w/ a uv light, but when i did it got everywhere and it was just a waste of money. if the system is empty and you know there's a leak, i would start by replacing the o-rings (they're usually the first culprit if there's no visible tears). sounds like the guy that sold you the car tried to fill it, which means the car may already be set up for r134.

[eyezpinned]

one more thing, i'm not suggesting you waste freon, but the first thing most people do is see if the system needs a recharge before replacing the o rings etc. of course you would do a visual inspection, but sometimes all it needs is a refill. after you conclude the system isnt holding a charge is when i think it warrants replacing the o rings and dye. then your gonna have to fill it again. also evacuation is mostly for the disposal of r12 (ozone killer). your system can be purged by hand and work fine. the leftover compressor oils can mix, it's the gasses that dont get along

[ninjajim4]

discharging a system has nothing whatsoever to do with evacuating. they're two completely different processes. if you have a leak that you can actually HEAR, you've got a BAD leak. most times you wont hear a thing, and your freon is gone within the week.

http://autoactraining.com/artman/publis ... _106.shtml" onclick="window.open(this.href);return false;

[Mazdaspeed96743]

Oh I see, thanks.

[Daninski]

Usually nitrogen is used to pressurize the system so you can use soapy water to find the leak. If there's a little oil on the line this could indicate where the leak is. It could be in your condensor (front of rad) in which case be prepared to pay. Hopefully it's not in the evaporator (in with your heater core) . They do sell refridgerant with a sealer but that only works for small leaks, not rotted out condensors or lines. Finally, move to Canada, we're always cooool.