Another A/C question
07-17-2002, 08:40 PM
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Another A/C question
Hi everyone,
In the UK summer we are currently having our 2-3 days of warmish weather for the year.
So when I actually need it my A/C appears to be working intermittantly. <img src="graemlins/cussing.gif" border="0" alt="[grrrrrrr]" />
I have done a search and my symptoms do not match those posted as far as I can tell.
My A/C either blows cold or not and does not appear to be related to oil temperature. It appears to work sometimes and not others for no apparent reason. But once or twice I managed to get it to cool by simply turning the ignition off and on again.
Any thoughts?
My guessess are:
1,wiring harness
2,solenoid valve to the left of engine cooling fan :mentioned by Ray in a previous post relating to vacumm controls
3, the oft mentioned resistors (may be I just missed the pattern)
4,the evaporator has been mentioned as a past cause of a/c woes
5, the climate control computer - oh no!
I guess I will have to get it looked at in case the weather holds up (and its damm embarrassing - if I have to hear 'my golf's a/c cools much better than this' one more time).
Cheers
Tito.
c2 '94
In the UK summer we are currently having our 2-3 days of warmish weather for the year.
So when I actually need it my A/C appears to be working intermittantly. <img src="graemlins/cussing.gif" border="0" alt="[grrrrrrr]" />
I have done a search and my symptoms do not match those posted as far as I can tell.
My A/C either blows cold or not and does not appear to be related to oil temperature. It appears to work sometimes and not others for no apparent reason. But once or twice I managed to get it to cool by simply turning the ignition off and on again.
Any thoughts?
My guessess are:
1,wiring harness
2,solenoid valve to the left of engine cooling fan :mentioned by Ray in a previous post relating to vacumm controls
3, the oft mentioned resistors (may be I just missed the pattern)
4,the evaporator has been mentioned as a past cause of a/c woes
5, the climate control computer - oh no!
I guess I will have to get it looked at in case the weather holds up (and its damm embarrassing - if I have to hear 'my golf's a/c cools much better than this' one more time).
Cheers
Tito.
c2 '94
07-23-2002, 08:58 PM
#2
Instructor
[quote]Originally posted by Tito:
<strong>Hi everyone,
In the UK summer we are currently having our 2-3 days of warmish weather for the year.
So when I actually need it my A/C appears to be working intermittantly. <img src="graemlins/cussing.gif" border="0" alt="[grrrrrrr]" />
I have done a search and my symptoms do not match those posted as far as I can tell.
My A/C either blows cold or not and does not appear to be related to oil temperature. It appears to work sometimes and not others for no apparent reason. But once or twice I managed to get it to cool by simply turning the ignition off and on again.
Any thoughts?
My guessess are:
1,wiring harness
2,solenoid valve to the left of engine cooling fan :mentioned by Ray in a previous post relating to vacumm controls
3, the oft mentioned resistors (may be I just missed the pattern)
4,the evaporator has been mentioned as a past cause of a/c woes
5, the climate control computer - oh no!
I guess I will have to get it looked at in case the weather holds up (and its damm embarrassing - if I have to hear 'my golf's a/c cools much better than this' one more time).
Cheers
Tito.
c2 '94</strong><hr></blockquote>
Check your freon charge, low charge can cause an intermittant cooling, secondly, check you expansion valve, it could be mulfunctioning.
Good luck,
Andrew #020729-2922
<strong>Hi everyone,
In the UK summer we are currently having our 2-3 days of warmish weather for the year.
So when I actually need it my A/C appears to be working intermittantly. <img src="graemlins/cussing.gif" border="0" alt="[grrrrrrr]" />
I have done a search and my symptoms do not match those posted as far as I can tell.
My A/C either blows cold or not and does not appear to be related to oil temperature. It appears to work sometimes and not others for no apparent reason. But once or twice I managed to get it to cool by simply turning the ignition off and on again.
Any thoughts?
My guessess are:
1,wiring harness
2,solenoid valve to the left of engine cooling fan :mentioned by Ray in a previous post relating to vacumm controls
3, the oft mentioned resistors (may be I just missed the pattern)
4,the evaporator has been mentioned as a past cause of a/c woes
5, the climate control computer - oh no!
I guess I will have to get it looked at in case the weather holds up (and its damm embarrassing - if I have to hear 'my golf's a/c cools much better than this' one more time).
Cheers
Tito.
c2 '94</strong><hr></blockquote>
Check your freon charge, low charge can cause an intermittant cooling, secondly, check you expansion valve, it could be mulfunctioning.
Good luck,
Andrew #020729-2922
07-23-2002, 11:31 PM
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Tito, I will actually suggest the exact opposite solution.
Sunday, I was on the way back from a weekend of track driving. Temp was 92+ F, high humidity. Car stays decently cool for the first hour. Then, gets progressively warmer. I stop, pick up some R134A and charging kit (including pressure gauge). Check pressure using low side. Nothing. Add what I think is a full can of freon. Nothing. I notice that the compressor is cycling on for about 1 - 2 seconds every 15 seconds or so, even with the A/C on high. Go back to the parts store, get another can of freon (this one much fuller). However, the compressor isn't cycling long enough to draw in the freon from the can.
Decide to keep driving home, then realize that the compressor is probably shutting itself off to keep from overpressurizing. Pull over, find a cotter pin (from the tire trailer I'm pulling). Running the A/C on high, I discharge some freon (and slimy oil, of course) from the low pressure inlet until the compressor stays on.
Bingo. The compressor stays on, the car is now ice box cool for the ride home. Much cooler than it's been during the last two years.
Turns out that the system was overcharged either from the factory or the previous owner. Driving in the hot for an hour with the compressor running got the pressures way too high, so the thing was cycling off and progressively loosing cooling capability.
Check your compressor clutch while the engine is running and with the A/C being on immediately after startup. If the compressor runs for a good while before cycling off, and the car is cold, then your have at least the pressure needed to cool. Then, run the A/C for awhile and when you notice the car getting warmer inside, check to see if the compressor is cycling on/off regularly. If so, I'd bet that the system is overpressurized. Unscrew the lower black cap for the low pressure side (should be the fat pipes vs. the skinny pipes and should be cold vs. hot) and let out some pressure.
Oh, the reason the gauge didn't work is that it doesn't open the valve behind the black cap. Porsche must have some proprietary system. Also, because of this, I never actually got any of the freon I bought into the system.
Hope this helps. Sorry for the excessive length.
Sunday, I was on the way back from a weekend of track driving. Temp was 92+ F, high humidity. Car stays decently cool for the first hour. Then, gets progressively warmer. I stop, pick up some R134A and charging kit (including pressure gauge). Check pressure using low side. Nothing. Add what I think is a full can of freon. Nothing. I notice that the compressor is cycling on for about 1 - 2 seconds every 15 seconds or so, even with the A/C on high. Go back to the parts store, get another can of freon (this one much fuller). However, the compressor isn't cycling long enough to draw in the freon from the can.
Decide to keep driving home, then realize that the compressor is probably shutting itself off to keep from overpressurizing. Pull over, find a cotter pin (from the tire trailer I'm pulling). Running the A/C on high, I discharge some freon (and slimy oil, of course) from the low pressure inlet until the compressor stays on.
Bingo. The compressor stays on, the car is now ice box cool for the ride home. Much cooler than it's been during the last two years.
Turns out that the system was overcharged either from the factory or the previous owner. Driving in the hot for an hour with the compressor running got the pressures way too high, so the thing was cycling off and progressively loosing cooling capability.
Check your compressor clutch while the engine is running and with the A/C being on immediately after startup. If the compressor runs for a good while before cycling off, and the car is cold, then your have at least the pressure needed to cool. Then, run the A/C for awhile and when you notice the car getting warmer inside, check to see if the compressor is cycling on/off regularly. If so, I'd bet that the system is overpressurized. Unscrew the lower black cap for the low pressure side (should be the fat pipes vs. the skinny pipes and should be cold vs. hot) and let out some pressure.
Oh, the reason the gauge didn't work is that it doesn't open the valve behind the black cap. Porsche must have some proprietary system. Also, because of this, I never actually got any of the freon I bought into the system.
Hope this helps. Sorry for the excessive length.