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AC compressor cuts on and off


Seanpowers83
12-14-2009, 09:24 AM
Hey guys. New to this forum. I have a 95 stang that I just had refilled with freon and oil at Ice Cold Air. The compressor turns on then cuts off as if its low on freon but its not. Last night the ac started blowing cold and was this morning then started back on the compressor turning on then off. I know it has freon in it and is full. Could it be that the orifice tube is clogged or maybe even the drier? is this something that I could take off and try to clean out? Any help is greatly appreciated.

Sean

MagicRat
12-14-2009, 09:36 AM
Did they just refill it, or did they actually service it properly?

A proper servicing includes fixing whatever component caused the leak in the first place, evacuating the system, replacing the drier (or exposing it to vacuum for a few hours) etc.

Generally, there is no servicing the owner can do because of the special equipment required for testing and repair.

IMO take it back to Ice Cold Air. If they did service it properly, they can test the high and low pressure ports to see what is going on.

Seanpowers83
12-14-2009, 03:12 PM
Thanks for quick reply. I actually bought the car a couple months ago and previous owner said the a/c just stopped working. I then took it to ice cold air to see if it was due to freon. The guy there took all the freon out and replaced it. It actually didnt have a leak. After that it never worked but all of a sudden last night it started working then quit today. The compressor just turns on then right back off as if its not getting enough freon. Thats why I was thinking the orifice tube may just be clogged.

Seanpowers83
12-14-2009, 03:19 PM
Also what do you mean by exposing the drier to a vacuum? Could it be the drier that is bad? Last night was the first time it worked and it pratically blew out ice cubes it was so cold.

Thx

jd-autotech
12-14-2009, 03:22 PM
you could have a bad connection at the a/c cycle switch its the sensor on the accummulator

Seanpowers83
12-14-2009, 04:01 PM
Could you tell me exactly where this switch is? Is that the connector on the drier in the back left of the engine bay when standing in front of car looking at engine? This help is greatly appreciated.

Thanks again
Sean

fordtrucksonly
12-15-2009, 01:40 AM
1 of 3 things,

1) accumulator switch bad connection or bad switch
2) too much or not enough refrigerant/oil
3)compressor might have gone bad. and is now locking up.

hrdbdy38
12-15-2009, 02:14 AM
I kind of have the same problem with my 1990 Ford Mustang 5.0.(with manual 5 speed)

I serviced my AC this summer as well and did it properly. I evacuated old freon and filled it with proper amount of freon and oil (as the pressure is right on).

Whenever I have my fan on (with the AC OFF) the stupid AC pump cycles ON and OFF repeatedly. It would be no big deal but it also does it when I'm idling at a stoplight waiting for it to turn green. Occasionally my car dies because of it.

Big pain in my ass and even embarrassing at times.

How'd I fix my problem?

I just unplugged the top plug + wire going to my AC compressor. Now it can't cycle on and off lol.


It might not be the right way to do it - I'd be interested to see what is - but its fast, easy, and FREE.

fordtrucksonly
12-15-2009, 08:37 AM
Top plug is the accumulator switch.

hrdbdy38
12-16-2009, 02:11 PM
FORDTRUCKSONLY-- couple questions for you:


1- is it going to hurt my AC components with my switch unplugged all winter?

2- does the on/off cycling I have with my AC unit (when not being used) mean I need a new switch or is this cycling normal?

3- If I do need a switch, is this something that's easy to change, or is it easier just to change the whole compressor?

thanks for the help

fordtrucksonly
12-16-2009, 10:49 PM
FORDTRUCKSONLY-- couple questions for you:


1- is it going to hurt my AC components with my switch unplugged all winter?

2- does the on/off cycling I have with my AC unit (when not being used) mean I need a new switch or is this cycling normal?

3- If I do need a switch, is this something that's easy to change, or is it easier just to change the whole compressor?

thanks for the help

Hey buddy,

I hope i can help,
1- No, it won't hurt anything to leave it unplugged, your defrost wont function properly because it uses the compressor. (IE: The compressor wont function if the switch is unplugged.)
2- The compressor will cut on/off constantly due to to much or not enough refrigerant, or a bad clutch on the compressor. (Is the clutch engaging and disengaging frequently?)
3- The switch is easy to change as long as you have pretty good mechanical know-how. You shouldn't have any problems... If you have any questions you can contact me.

Good luck, let me know.
Chris

hrdbdy38
12-17-2009, 02:17 AM
FTO -

thanks for being so quick! (Certified Ford Tech huh? NICE. Dont suppose u could answer my thread could u? the code 96 I'm getting on my 90 Mustang GT?)


In response to YOUR remarks -

re 2) Yes, when my wire is plugged in the clutch engages and disengages every 30 seconds - couple minutes. On/off, On/off, On/off....

re 3) I have lots of mechanical know how, especially with engines and transmissions, and most other car related stuff. Can I change the switch with the compressor where its at? Or do I need to remove my belt, unhook the refrigerant lines, THEN remove the compressor so I can change the switch?

Another question for you-

How do you test the parts to know if it's the clutch, or the switch that needs replaced?

thanks again,
K. Just :wink:

fordtrucksonly
12-17-2009, 09:19 AM
FTO -

thanks for being so quick! (Certified Ford Tech huh? NICE. Dont suppose u could answer my thread could u? the code 96 I'm getting on my 90 Mustang GT?)


In response to YOUR remarks -

re 2) Yes, when my wire is plugged in the clutch engages and disengages every 30 seconds - couple minutes. On/off, On/off, On/off....

re 3) I have lots of mechanical know how, especially with engines and transmissions, and most other car related stuff. Can I change the switch with the compressor where its at? Or do I need to remove my belt, unhook the refrigerant lines, THEN remove the compressor so I can change the switch?

Another question for you-

How do you test the parts to know if it's the clutch, or the switch that needs replaced?

thanks again,
K. Just :wink:

If the compressor is cycling frequently its overfilled, or clutch is bad. I would hook up some guages and check the refrigerant level. Sometimes a switch "can" cause it.

To change the switch is easy, no unhooking lines or anything just the switch will come out.

To test the switch is very easy, take a jumper wire and run it to the plug that plugs into the switch (directly from side to side on the plug) Turn a/c on and see if it stays engaged. If it still cycles you know the switch is good and the problem lies with the clutch or compressor. But if the compressor stays on the whole time its jumped the switch is faulty.

Hope this helps.
Chris

hrdbdy38
12-29-2009, 02:45 PM
FTO (Chris)-

I'm a little confused on your instructions below. Can u explain it a little better?

We are talking the switch on top of the AC unit correct? That has 2 prongs sticking out ? And where I have removed my wires with the female plug on the end?

Confused if you mean side to side on the 2 male ends, or if one of the jumpers has to go to the female plug (at end of the wires) that I unhooked?

thanks again,

K.Just





To test the switch is very easy, take a jumper wire and run it to the plug that plugs into the switch (directly from side to side on the plug) Turn a/c on and see if it stays engaged. If it still cycles you know the switch is good and the problem lies with the clutch or compressor. But if the compressor stays on the whole time its jumped the switch is faulty.

Hope this helps.
Chris

fordtrucksonly
12-29-2009, 11:59 PM
FTO (Chris)-

I'm a little confused on your instructions below. Can u explain it a little better?

We are talking the switch on top of the AC unit correct? That has 2 prongs sticking out ? And where I have removed my wires with the female plug on the end?

Confused if you mean side to side on the 2 male ends, or if one of the jumpers has to go to the female plug (at end of the wires) that I unhooked?

thanks again,

K.Just

No no no, I'm sorry, I wasn't thorough. The female plug (Harness) gets the jumper wire, basically you'll keep the switch on with the jumper. run the wire from one female end to the other female end on the plug itself. *** DON'T keep it like that, just to test only. ***

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