993 Air con problem
Discussion
Ok so its not workin. Anyone any ideas? Here's the symptoms:
1) On normal fan, say setting 2, air blows out normal.
2) Press the air con button.
3) noise starts to suggest air con is starting.
4) air continues to blow out of vents for a few seconds.
5) further noise sounding like vents/flaps closing.
6) no air at all now coming from anywhere.
7) the belt driven air con unit under the engine lid does not engage.
The following has been carried out:
7) New control unit put in dash to check if old unit is faulty - same problem.
8) Air con pressure checked - NIL!
9) Air con regassed - 840g put in per manual.
10)Test again - points 1) to 6) happen again.
11) Point 7) - the air con unit engages and spins then stops when flaps/vents close.
Other points to note:
12) After 4 hours the system only had 540g left in - therefore a leak?
13) When the engine is switched off but the ignition on, after points 1) to 4) the system carries on normally with point 5) not occuring. Does this mean that air con air is coming through the vents or normal air?
Q) Would the possible leak stop the system from working even immediately after re-gassing?
Q) What else could be the problem?
Q) Potential cost to fix?
Thanks for any help.
1) On normal fan, say setting 2, air blows out normal.
2) Press the air con button.
3) noise starts to suggest air con is starting.
4) air continues to blow out of vents for a few seconds.
5) further noise sounding like vents/flaps closing.
6) no air at all now coming from anywhere.
7) the belt driven air con unit under the engine lid does not engage.
The following has been carried out:
7) New control unit put in dash to check if old unit is faulty - same problem.
8) Air con pressure checked - NIL!
9) Air con regassed - 840g put in per manual.
10)Test again - points 1) to 6) happen again.
11) Point 7) - the air con unit engages and spins then stops when flaps/vents close.
Other points to note:
12) After 4 hours the system only had 540g left in - therefore a leak?
13) When the engine is switched off but the ignition on, after points 1) to 4) the system carries on normally with point 5) not occuring. Does this mean that air con air is coming through the vents or normal air?
Q) Would the possible leak stop the system from working even immediately after re-gassing?
Q) What else could be the problem?
Q) Potential cost to fix?
Thanks for any help.
993 air con is shite. They all fail eventually. The condensor at the front of the car corrodes to buggery and that is the usual cause of leaks. All 3 of my 993s had this problem, I paid around £500 to replace the condensor and re-gas last time. It happens all the time and therefore isn't a monster labour job to fix.
The flaps are another kettle of fish... you don't want those to fail because it's a lot of labour to remove the dash etc. and get to them. Given that the aircon compressor solenoid is activating and the pump is working, the rest of the system could be OK (you'd still not get cold air if the condensor was rotten).
If the flaps are shutting off the air flow completely though there may be other problems...
The flaps are another kettle of fish... you don't want those to fail because it's a lot of labour to remove the dash etc. and get to them. Given that the aircon compressor solenoid is activating and the pump is working, the rest of the system could be OK (you'd still not get cold air if the condensor was rotten).
If the flaps are shutting off the air flow completely though there may be other problems...
Does the same thing happen (lots of fan noise but no airflow) when you try the recirc button with the AC off?
If yes the cause may be a disconnected vacuum line going from the engine compartment to the climate control system? Any work done in the engine compartment lately?
On my 993tt the line is made of hard black plastic and is on the left side where it seems to disappear into the wiring loom.
You may well have a freon leak as well but the airflow problem sounds like one that needs to be sorted.
If yes the cause may be a disconnected vacuum line going from the engine compartment to the climate control system? Any work done in the engine compartment lately?
On my 993tt the line is made of hard black plastic and is on the left side where it seems to disappear into the wiring loom.
You may well have a freon leak as well but the airflow problem sounds like one that needs to be sorted.
I've had similar problems with mine - The control unit seems to have a life of it's own. Loads of air (warm of course!) on recirc, and nothing on normal. Engage the aircon (small snowflake) and there's no perceivable difference in temperature or flow, engage the big f**k-off snowflake and the systems cuts in and out every 15 seconds.
I'm almost certain I have a bad condenser (i.e. leaking) but at 500 quid plus labour (me and spanners don't go together) I'm not booking it in given that I'm not one of the GT3/TT-owning change-my-car-on-a-whim money-no-object people who post here
Mine was re-gassed a few weeks ago, a vacuum test was done which indicated that there were no leaks, but now there's not even enough gas in the system to engage the clutch on the compressor.
The system is crap because the component parts are spread out all over the car - The compressor is about as far from the condenser as it could be, and the evaporator is buried behind the dash requiring the fuel tank to come out if it needs looking at (about 6 hours labour apparently).
The reason that so many 993's are advertised without working air-con is that when it goes wrong people hear these horror stories and can't be arsed to spend potentially one to two grand to get it fixed.
At the ene of the day the 993 is a brilliant piece of kit - I love mine to bits - but the niggling faults can get a little tiresome.
Chris
I'm almost certain I have a bad condenser (i.e. leaking) but at 500 quid plus labour (me and spanners don't go together) I'm not booking it in given that I'm not one of the GT3/TT-owning change-my-car-on-a-whim money-no-object people who post here
Mine was re-gassed a few weeks ago, a vacuum test was done which indicated that there were no leaks, but now there's not even enough gas in the system to engage the clutch on the compressor.
The system is crap because the component parts are spread out all over the car - The compressor is about as far from the condenser as it could be, and the evaporator is buried behind the dash requiring the fuel tank to come out if it needs looking at (about 6 hours labour apparently).
The reason that so many 993's are advertised without working air-con is that when it goes wrong people hear these horror stories and can't be arsed to spend potentially one to two grand to get it fixed.
At the ene of the day the 993 is a brilliant piece of kit - I love mine to bits - but the niggling faults can get a little tiresome.
Chris
Edited by welshchris on Friday 14th July 00:02
Yup, it cost me quite a bit (can't exactly remember how much) to get mine completely fixed, including a new evaporator, the old one having corroded. The good news is that I took the 993 to an a/c specialist who charged me half what most others would have as labour was much cheaper and he sourced a third party part.
He did an excellent job and then - I went and sold the car! D'Oh!
He did an excellent job and then - I went and sold the car! D'Oh!
manek said:
Yup, it cost me quite a bit (can't exactly remember how much) to get mine completely fixed, including a new evaporator, the old one having corroded. The good news is that I took the 993 to an a/c specialist who charged me half what most others would have as labour was much cheaper and he sourced a third party part.
He did an excellent job and then - I went and sold the car! D'Oh!
He did an excellent job and then - I went and sold the car! D'Oh!
...and bought an XJS in drag by the looks of things...
Hi,
My AC failed on the way to the ring a couple of weeks back and left Domster and I feeling a little on the warm side. The symptoms of the car going thru the motions re flaps and then the compressor not starting certainly sounds familiar.
I had the system emptied and we got 800g out but a shed load of moisture, vacuum tested the system (it failed with a slow leak) and regassed it with UV dye and it worked for precisely 1 hour before packing up again. (incidentally the chap at a local backstreet garage completed the regas/test etc for £30).
Anyway it seems the compressor gets locked out to avoid damage from low oil if the refrigerant levels drop and it appears that it doesn't need to be by much for it to stop engaging..
We think the evaporator may be shot or alternatively a seal has blown as the condensor and drier are fairly new and it is booked in to a local indy who is going to fettle it over the next few days.
Will keep all posted.
KR,
Ian D
My AC failed on the way to the ring a couple of weeks back and left Domster and I feeling a little on the warm side. The symptoms of the car going thru the motions re flaps and then the compressor not starting certainly sounds familiar.
I had the system emptied and we got 800g out but a shed load of moisture, vacuum tested the system (it failed with a slow leak) and regassed it with UV dye and it worked for precisely 1 hour before packing up again. (incidentally the chap at a local backstreet garage completed the regas/test etc for £30).
Anyway it seems the compressor gets locked out to avoid damage from low oil if the refrigerant levels drop and it appears that it doesn't need to be by much for it to stop engaging..
We think the evaporator may be shot or alternatively a seal has blown as the condensor and drier are fairly new and it is booked in to a local indy who is going to fettle it over the next few days.
Will keep all posted.
KR,
Ian D
welshchris said:
The system is crap because the component parts are spread out all over the car - The compressor is about as far from the condenser as it could be, and the evaporator is buried behind the dash requiring the fuel tank to come out if it needs looking at (about 6 hours labour apparently).
Being a rear engined car that's pretty much the way it has to be. Compressor needs to be at the engine, condenser needs to be where there's loads of cool airflow (earlier 911's have the condenser attached to the engine lid which isn't the coolest area on a 911 in traffic) and the evaporator is under the base of the windscreen where the interior fan and air distribution system is. It's not a bug, it's a feature!
That the car appears to have been constructed around the evaporator is rather unfortunate though.
996/7's and Boxsters have two condensers up front and they seem to be a bit more prone to stone damage; pity them!
Edited by phelix on Friday 14th July 11:40
Marquis_Rex said:
manek said:
Yup, it cost me quite a bit (can't exactly remember how much) to get mine completely fixed, including a new evaporator, the old one having corroded. The good news is that I took the 993 to an a/c specialist who charged me half what most others would have as labour was much cheaper and he sourced a third party part.
He did an excellent job and then - I went and sold the car! D'Oh!
He did an excellent job and then - I went and sold the car! D'Oh!
...and bought an XJS in drag by the looks of things...
Forgive them Lord, for they know not what they say!
Edited by manek on Tuesday 18th July 21:43
997gt3 said:
993AL said:
I need a condenser for my 993, I contacted someone who supplies all aircon parts through an advert on Ebay,was quoted £156 incl VAT and Del.
Would you mind shedding some light on this supplier - contact details or ebay details please?
No problem, this is the link to Ebay item
http://cgi.ebay.co.uk/Porsche-Air-Con
Good luck
997gt3 said:
Ok so its not workin. Anyone any ideas? Here's the symptoms:
1) On normal fan, say setting 2, air blows out normal.
2) Press the air con button.
3) noise starts to suggest air con is starting.
4) air continues to blow out of vents for a few seconds.
5) further noise sounding like vents/flaps closing.
6) no air at all now coming from anywhere.
7) the belt driven air con unit under the engine lid does not engage.
The following has been carried out:
7) New control unit put in dash to check if old unit is faulty - same problem.
8) Air con pressure checked - NIL!
9) Air con regassed - 840g put in per manual.
10)Test again - points 1) to 6) happen again.
11) Point 7) - the air con unit engages and spins then stops when flaps/vents close.
Other points to note:
12) After 4 hours the system only had 540g left in - therefore a leak?
13) When the engine is switched off but the ignition on, after points 1) to 4) the system carries on normally with point 5) not occuring. Does this mean that air con air is coming through the vents or normal air?
Q) Would the possible leak stop the system from working even immediately after re-gassing?
Q) What else could be the problem?
Q) Potential cost to fix?
Thanks for any help.
1) On normal fan, say setting 2, air blows out normal.
2) Press the air con button.
3) noise starts to suggest air con is starting.
4) air continues to blow out of vents for a few seconds.
5) further noise sounding like vents/flaps closing.
6) no air at all now coming from anywhere.
7) the belt driven air con unit under the engine lid does not engage.
The following has been carried out:
7) New control unit put in dash to check if old unit is faulty - same problem.
8) Air con pressure checked - NIL!
9) Air con regassed - 840g put in per manual.
10)Test again - points 1) to 6) happen again.
11) Point 7) - the air con unit engages and spins then stops when flaps/vents close.
Other points to note:
12) After 4 hours the system only had 540g left in - therefore a leak?
13) When the engine is switched off but the ignition on, after points 1) to 4) the system carries on normally with point 5) not occuring. Does this mean that air con air is coming through the vents or normal air?
Q) Would the possible leak stop the system from working even immediately after re-gassing?
Q) What else could be the problem?
Q) Potential cost to fix?
Thanks for any help.
I am not an expert but recently went through a similar scenario on my 993. It looks like you have at least 2 problems:
1. definitely a leak - maybe just a seal. If you get it regassed with dye, you may be able to trace where it is finding it's way out. Ball ache finding all the places it could leak, though.
2. the vacuum pipe that phelix referred to may be disconnected. When you hit the aircon button (or the recirc button) the flaps and vents in point 5) close off the external air intakes, and at the same time operates an electrical solenoid valve which connects aforementioned vacuum pipe to the "vacuum capsule with bypass air flaps". This operates with a "thunk" noise rather than a gradual hiss that may be heard when other vents are closing gradually, and ports the now closed off chamber to the cold bit of the aircon unit. So no "thunk" - means fans sucking from closed chamber, sounds like point 6). Check under the bonnet by removing the long plastic cover (between the fusebox and the windscreen) that covers the pollen filters etc - on the drivers side (RHD) there will be a small black solenoid looking jobby which should have a couple of small black shiny tubes (2 or 3mm dia ) connected to it via some fatter bent rubber hose. One comes from the engine bay (source of vacuum), the other heads off to the bypass air flap unit. If either of these is disconnected the bypass flap will not operate. To check if you have vacuum just pull a pipe out of the rubber and place the open end against your tongue or a wet finger (the engine must be running and only one pipe will have vacuum). If you don't get vacuum, then the pipe is likely to be disconnected engine end (not sure where though, but likely on the inlet/varioram assembly).
On mine, the pipes had simply been pulled out so just poking them back in to the rubber connectors gave me control again. It took me an age to work this out because the manual is not very good on troubleshooting. I believe replacing the bypass flap unit is a major task so I hope you don't find that to be faulty.
As promised an update on my aircon...
After several weeks of my aircon compressor working when it felt like it, my car is finally fixed.
The issue was traced to a dodgy positive connection to the aircon compressor relay in the front fusebox.
Apparently if a relay or fuse is disturbed, sometimes plugging it back in can push the connector back into the depths of the fusebox so it will only make an intermittent connection on the bottom of the blade. When coupled with spirited driving and warm weather making insulated cables more flexible and less likely to be applying the requisite pressure to complete the circuit, no end of strange faults can appear and disappear at will.
The aircon system works on a switched earth so no fault codes showed on the Bosch Hammer which certainly had us foxed for a while.
Also the leak under vacuum when the system was refilled didn't actually exist and when the system was pressure tested, it passed with flying colours.
So what sounded like it was going to be a new evaporator and a bill for well over a grand actually cost me £20 for a relay (belt and braces) together with a few hours of labour with a multimeter and a wiring diagram.
I must praise my indy for his persistance and use of logic rather than just randomly changing parts until the problem went away and this is definitely something to check yourself with any intermittent electrical fault.
KR,
Ian D
After several weeks of my aircon compressor working when it felt like it, my car is finally fixed.
The issue was traced to a dodgy positive connection to the aircon compressor relay in the front fusebox.
Apparently if a relay or fuse is disturbed, sometimes plugging it back in can push the connector back into the depths of the fusebox so it will only make an intermittent connection on the bottom of the blade. When coupled with spirited driving and warm weather making insulated cables more flexible and less likely to be applying the requisite pressure to complete the circuit, no end of strange faults can appear and disappear at will.
The aircon system works on a switched earth so no fault codes showed on the Bosch Hammer which certainly had us foxed for a while.
Also the leak under vacuum when the system was refilled didn't actually exist and when the system was pressure tested, it passed with flying colours.
So what sounded like it was going to be a new evaporator and a bill for well over a grand actually cost me £20 for a relay (belt and braces) together with a few hours of labour with a multimeter and a wiring diagram.
I must praise my indy for his persistance and use of logic rather than just randomly changing parts until the problem went away and this is definitely something to check yourself with any intermittent electrical fault.
KR,
Ian D
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