A/C Problems.....

[Jacob_Royer]

Ok when i bought the mustang the a/c didnt work but it was cold outside... Yesterday i added 2 cans of pre-mixed 134a (refridgerant+oil) and it worked GREAT! ice cold!! Well today i get in and no a/c... pressure is still in the blue on my cheapo guage but the compressor is not kicking in! what now?? i tried to add a hair more freon and it didnt do anything at all... Compressor clutch??

 

[Jacob_Royer]

BTW the compressor spins freely and so does the clutch.. Is there possibly a fuse or relay somwhere that could have gone south?

 

[Spro]

It is possible that it is not turning on due to low or high pressure in the system. You wont get an accurate reading on the guage with the compressor not running. Now, before you added the refrigerant how much did you have left in the system before you added any? Im thinking you have a pretty good leak which brought the pressure down low enough where the compressor wont start. I checked mine while it was off in my garage at 65 degrees and my guage showed 60 psi. Heres a pic of the guage that I have. Hope this helps out.

 

[Jacob_Royer]

I was right at 25 when i charged it enough to work.. sat over night after running all day, then next day NOTHING! argh!! So i think maybe i have a leak?? maybe i didnt have enough in there anyway? so i add a little more.. and the compressor wont ever kick on! now its sitting on 32 with the compressor not kicking on at all.

 

[COramprat]

If the pressure is good then it could be the clutch...I can't remember how to check it though.

For the clutch replacement do a search for compressor clutch under my screen name. I replaced mine a few years back.

 

[Will Smith]

It is possible that it is not turning on due to low or high pressure in the system. You wont get an accurate reading on the guage with the compressor not running. Now, before you added the refrigerant how much did you have left in the system before you added any? Im thinking you have a pretty good leak which brought the pressure down low enough where the compressor wont start. I checked mine while it was off in my garage at 65 degrees and my guage showed 60 psi. Heres a pic of the guage that I have. Hope this helps out.

if when u checked your gauge when the vehicle was off and it read 60psi then u have a leak somewhere in the system. When an a/c system is turned off the high and low sides will equalize out... normally its around 80-100psi. when the vehicle runs the low side drops to about 32-35 on the low side and around 200 on the high. what i do recommend is either take your car to a good a/c shop/or dealership. or invest in a a/c Dye light and A/c glasses. if you do the later make sure to check all lines and connections for leaks. You may want to remove the front 8mm bolt on the compressor and pull the clutch plate out to see if you have dye on it and check the Evaporator case drain for signs of dye.

 

[blackink00]

the compressor wont kick on with a static pressure under like 40psi. but most likely you have a leak. take it into a shop and have them diagnos it. unless you have the proper equipment and know what your doing you shouldnt work on your ac system. they are very sensitive to how much refridgerent you add and moisture and all that stuff. just take it in.

 

[Mustang5L5]

More than likely a leak somewhere

 

[the98stang]

If the compressor is not kicking on, it might be your cycle switch. Remove the cycle switch (passenger firewall area) and short it with a paper clip for a few seconds. If the compressor kicks on, your switch it bad. Replace the switch and all should be fine.

 

[Will Smith]

the pressures dont indicate a short in a switch... i would recommend starting with the leak in the system since it will be the large $$ amount here... get that resolved and then if u still have problem then go to your electronics...

 

[the98stang]

the pressures dont indicate a short in a switch... i would recommend starting with the leak in the system since it will be the large $$ amount here... get that resolved and then if u still have problem then go to your electronics...

Why would you try to fix the most expensive part first? A new switch is like $10 from the dealer anyway. And testing the switch is FREE. It's not uncommon for the cycle switches to fail on these cars as well. I'm telling you if the compressor is not kicking on it's worth 5 minutes of your time to short the switch to see if it's the issue.

 

[Will Smith]

Why would you try to fix the most expensive part first? A new switch is like $10 from the dealer anyway. And testing the switch is FREE. It's not uncommon for the cycle switches to fail on these cars as well. I'm telling you if the compressor is not kicking on it's worth 5 minutes of your time to short the switch to see if it's the issue.

due to the low, low side reading that he posted a picture up of the system has a leak...there is no doubt bout it....the reading should be atleast 80-100 or so with the vehicle's a/c not running...im very familiar with these vehicle since i do work as a tech at a ford dealer... the problem he has first is a leak in the system... the system will need to be charge and sealed before other diag on electrical systems are checked...

 

[the98stang]

due to the low, low side reading that he posted a picture up of the system has a leak...there is no doubt bout it....the reading should be atleast 80-100 or so with the vehicle's a/c not running...im very familiar with these vehicle since i do work as a tech at a ford dealer... the problem he has first is a leak in the system... the system will need to be charge and sealed before other diag on electrical systems are checked...

Sorry I didn't realize that picture posted was of his exact pressure reading...

 

[Will Smith]

the static pressure on the low side needs to be atleast 60 or so for it to even kick on...and with the vehicle off that low side should go to atleast 80-90 or so....