• Welcome to the Contour Enthusiasts Group, the best resource for the Ford Contour and Mercury Mystique.

    You can register to join the community.

A/C question

A

AliasJerk

Addicted CEG'er
Joined
Oct 13, 2003
Messages
8,525
The other day really was the first time it was warm enough to test out the A/C, turned it on, heard the A/C compressor make its "click" noise, motor revved up about 250 rpms every 10 seconds, air didn't get cold.

so I tested a couple of things, checked if there was any leaks in the system by putting a pressure tester on the A/C line, A/C was perfectly pressurized, so I know its not because of low R134a. So I poped the hood, turned the A/C on and noticed something a little odd. Whenever the A/C compressor kicks on, I can hear a deep note coming from the air intake, it almost sounds like a half a second long "Moose"

I am also wondering, if the motor is revving up too much whenever the a/c turns on, which leads me to believe that the clutch inside of the compressor is done for, so when the A/C trys to come on the compressor never actually engages, yet the engine still trys to compensate for the extra power needed to run the A/C system, which would explain why the engine revs up a little bit every 10 seconds.

thoughts? Opinions?
 
did you use the proper gauges and check the low and high side pressures, most likely not :nonono:


sounds like your low on R-134A, but we will not know until we know and understand the pressures on the low and high sides of the system ...
 
BrApple said:
did you use the proper gauges and check the low and high side pressures, most likely not :nonono:


sounds like your low on R-134A, but we will not know until we know and understand the pressures on the low and high sides of the system ...
Click to expand...

I know your stance on charing your own A/C system, I dont do it because I know I dont properly know how too. I have an A/C charge cannister that has a valve on it and a gauge to test and see how much pressure is in the system, I only used the A/C cannister to test the pressure, no charge was applied. However, I was unable to test the pressure of the system on the passenger side of the car ( I dont know if this one is high or low), but I was able too on the driver side, which according to my gauge read as a good fill.
 
A single gauge is, unfortunately, pretty close to worthless unless it is provided in adequate context. Color bands on the el-cheapo gauges are even less useful. Specific pressure numbers are what is needed.

If the compressor clutch is not engaging and the el-cheapo gauge still reads in the "good" range, guess what--- the system is undercharged due to a leak.

Steve
 
projectSHO89 said:
A single gauge is, unfortunately, pretty close to worthless unless it is provided in adequate context. Color bands on the el-cheapo gauges are even less useful. Specific pressure numbers are what is needed.

If the compressor clutch is not engaging and the el-cheapo gauge still reads in the "good" range, guess what--- the system is undercharged due to a leak.

Steve
Click to expand...

well actually, the gauge did something good for me, I ran the A/C while the gauge was plugged in, and whenever the compressor kicked on, the gauge went down to the "low" section, then right back up again. So thats a good indicator that the system is working.

I will take it to a shop and have the A/C filled properly, thanks guys :)
 
AliasJerk said:
I know your stance on charing your own A/C system, I dont do it because I know I dont properly know how too. I have an A/C charge cannister that has a valve on it and a gauge to test and see how much pressure is in the system, I only used the A/C cannister to test the pressure, no charge was applied. However, I was unable to test the pressure of the system on the passenger side of the car ( I dont know if this one is high or low), but I was able too on the driver side, which according to my gauge read as a good fill.
Click to expand...


if you don't know how why are you doing it :confused:


fyi the low pressure side by the battery has a smaller fitting then the high pressure side, by the coolant tank ....
 
Last edited:
AliasJerk said:
well actually, the gauge did something good for me, I ran the A/C while the gauge was plugged in, and whenever the compressor kicked on, the gauge went down to the "low" section, then right back up again. So thats a good indicator that the system is working.

I will take it to a shop and have the A/C filled properly, thanks guys :)
Click to expand...


no that doesn't tell you that the system is working propperly. all it tells you is that the compressor is working. you don't know if the system has a leak, etc ...
 
Last edited:
BrApple said:
no that doesn't tell you that the system is working propperly. all it tells you is that the compressor is working. you don't know if the system has a leak, etc ...
Click to expand...

either way, the shop will be able to determine that when they charge the system correct?
 
surely.. after you pay 80$ (at least that is what it costs here) for a vacuum pull and charge... then when it leaks again, you'll have your answer.
 
I've got to check mine for leaks soon. I had my R134A refilled at the end of last summer and my A/C is back to being no different than the "fan" setting :blackeye: Maybe an interesting trade will get someone local who is experienced in such things to help me out again :)
 
hotdimmes said:
I've got to check mine for leaks soon. I had my R134A refilled at the end of last summer and my A/C is back to being no different than the "fan" setting :blackeye: Maybe an interesting trade will get someone local who is experienced in such things to help me out again :)
Click to expand...


i would need to get new gauges or at least holes for my gauges but I know ctmystique has a set also, as well as a vacuum pump which you know already ...
 
Well if it were very low or almost out of freon the compressor would not kick on since the low pressure switch would keep the clutch from engaging. Also if it were low of freon but not out it would be cycling like crazy due to the low pressure switch not seeing the correct pressure.
If the compresoor is kicking on okay, then grab the suction line close to the firewall where it gets connected to the evaporator, is this getting cold. If so you may want to check to see that the divertor door in the dash is not sticking.

If you do find it low on charge, look closely at the low pressure switch, they have a tendency to leak. You can tell since there will be an accumulation of oil around the plastic part of the switch.
 
Last edited:
BrApple said:
i would need to get new gauges or at least holes for my gauges but I know ctmystique has a set also, as well as a vacuum pump which you know already ...
Click to expand...

Yeah, I was thinking maybe he'll take the heat shield as an offering. Also, if there were any small items you guys needed that I could buy for you, I wouldn't mind doing that. I'd rather support NECEG than some shop.
 
AliasJerk said:
well actually, the gauge did something good for me, I ran the A/C while the gauge was plugged in, and whenever the compressor kicked on, the gauge went down to the "low" section, then right back up again. So thats a good indicator that the system is working.

I will take it to a shop and have the A/C filled properly, thanks guys :)
Click to expand...

I was getting the same behaviour and I filled it with one of the auto parts recharge kits until it read in the full section. 3 weeks later still ice cold.
 
You must log in or register to reply here.
Back
Top