Air-conditioning system not releasing cold air
Thread Starter
AudiWorld Newcomer
Joined: Feb 2025
Posts: 1
Likes: 0
Air-conditioning system not releasing cold air
Compressor and condenser both working. When gas is loaded it takes less than 10 days and stops releasing cold air. Should go ahead checking leakages in the evaporator? Audi Q7 Sline 2013 model
AudiWorld Senior Member
Joined: Mar 2017
Posts: 1,616
Likes: 517
From: Fairbanks, Alaska
Someone mentioned a while back that there is a hard line in the A/C that runs along the left frame rail near the... front?... of the tire there. This can be a common location for abrasion, which is difficult to spot because the rest of the line looks perfectly fine. I'm not sure this could be your issue because of how long it takes to drain down.... but perhaps worth checking.
AudiWorld Super User
Joined: Jan 2021
Posts: 4,565
Likes: 1,456
From: USA - NM
Probably easiest just to add some UV dye or buy some freon with the UV dye included, etc., so you can more easily locate the leak(s) source. That's pretty much the 'standard' approach to locating A/C leaks.
Ten days is pretty quick, so it's a modest leak, and that being the case it's likely there could be some PAG oil residue at any leak locations...look for that too. The freon lines where they go in near the radiator housing is a fairly common point of failure from corrosion related to Winter road chemicals (pinhole leaks form), but in Malawi, not sure that would be an issue unless the car came from somewhere else; still, that's a good location to visually check out. Always check the A/C compressor just behind the belt pulley/clutch to see if signs of fresh leakage at the shaft seal on compressor, and of course peek at the hose connects off the compressor too. If that shaft seal is leaking on compressor, then that'd do it.
If you've noticed any odd odor inside the car after refilling the freon, and when the A/C is still blowing cold, then that is an indicator the leak is within the condenser inside the car, so the freon that escapes is passing directly into the car cabin.
Ten days is pretty quick, so it's a modest leak, and that being the case it's likely there could be some PAG oil residue at any leak locations...look for that too. The freon lines where they go in near the radiator housing is a fairly common point of failure from corrosion related to Winter road chemicals (pinhole leaks form), but in Malawi, not sure that would be an issue unless the car came from somewhere else; still, that's a good location to visually check out. Always check the A/C compressor just behind the belt pulley/clutch to see if signs of fresh leakage at the shaft seal on compressor, and of course peek at the hose connects off the compressor too. If that shaft seal is leaking on compressor, then that'd do it.
If you've noticed any odd odor inside the car after refilling the freon, and when the A/C is still blowing cold, then that is an indicator the leak is within the condenser inside the car, so the freon that escapes is passing directly into the car cabin.
Last edited by '10Q7TDI_Prestige'; Apr 10, 2025 at 01:50 PM.
AudiWorld Newcomer
Joined: Apr 2025
Posts: 2
Likes: 0
I have a 2018 A5. 107k. Same issue with my ac. Dealer and mechanic did not see a leak or other issues twice. Put Freon in twice but lasted about 2 weeks. Now they’re replacing evaporator because of leak. I’m not sure why they didn’t find it before. Cost around 2900. Apparently it’s a time consuming job/10hours or so they tell me.
Apparently Would have been under Audi special extended warranty if had less than 100k milage. 🤦🏻♂️
Apparently Would have been under Audi special extended warranty if had less than 100k milage. 🤦🏻♂️
AudiWorld Newcomer
Joined: Apr 2025
Posts: 2
Likes: 0
My A5 is a great car but I’ve had bad luck with it. Turbo had to be replaced around 80k miles and now ac evaporator. It’s so costly. I’m hoping it will go to 150 k before I buy another car. Most likely Not an Audi.
Club AutoUnion
Joined: Dec 2024
Posts: 512
Likes: 88
From: Chennai, India
The evaporator is probably a casualty. It becomes far less of a casualty when you change your cabin filter regularly or even earlier than Audi recommends. Especially if you're in a dusty or polluted environment with suspended dust or smog in the air, like your average big city.
Audi branded cabin filters are pretty cheap, a Mann or Hengist or whatever other third party is even cheaper. Evaporators are expensive and the labor + effort required to strip your dashboard is quite costly, plus once the dashboard is removed and reinstalled you are never going to have a manufacturer level fit and finish. Rattles and squeaks.
Audi branded cabin filters are pretty cheap, a Mann or Hengist or whatever other third party is even cheaper. Evaporators are expensive and the labor + effort required to strip your dashboard is quite costly, plus once the dashboard is removed and reinstalled you are never going to have a manufacturer level fit and finish. Rattles and squeaks.
AudiWorld Member
Joined: Sep 2021
Posts: 178
Likes: 84
Another concensus here, the evaporator seems to hide that there is a leak. Dealing with this on my recently acquired 2009 Cayman. Fortunately, buying the car from Carvana has paid off for me as everything has been covered under the Silverrock warranty.
In sequence, as that's how aftermarket warranties work. First compressor was replaced. Then EVAP valve (was dirty), then condensers as the Cayman has two mini ones (full of dirt and oil on the fins), then dryer (because of opening the system to many times, wanted to make sure there was no moisture in the system). Then the compressor again. Now replacing the evaporator. Like the guy with the A5, mine is a 8 hour or so job as you have to remove the entire dash to get to the Evaporator.
No UV detection system, faults, live meters, pointed to Evaporator.
AC systems is a pain. Best of luck and will follow this thread for my Q7.
In sequence, as that's how aftermarket warranties work. First compressor was replaced. Then EVAP valve (was dirty), then condensers as the Cayman has two mini ones (full of dirt and oil on the fins), then dryer (because of opening the system to many times, wanted to make sure there was no moisture in the system). Then the compressor again. Now replacing the evaporator. Like the guy with the A5, mine is a 8 hour or so job as you have to remove the entire dash to get to the Evaporator.
No UV detection system, faults, live meters, pointed to Evaporator.
AC systems is a pain. Best of luck and will follow this thread for my Q7.
Trending Topics
Club AutoUnion
Joined: Dec 2024
Posts: 512
Likes: 88
From: Chennai, India
First compressor was replaced. Then EVAP valve (was dirty), then condensers as the Cayman has two mini ones (full of dirt and oil on the fins), then dryer (because of opening the system to many times, wanted to make sure there was no moisture in the system). Then the compressor again. Now replacing the evaporator. Like the guy with the A5, mine is a 8 hour or so job as you have to remove the entire dash to get to the Evaporator.
If the AC is cooling well but the throw isn’t sufficient - the cold air just doesn’t reach your face - then it is either a blocked filter or a clogged condenser. If the AC doesn’t cool at all, or if you start getting condensation that looks like white Vapor in your vehicle’s cabin, most likely your evaporator.
Aircon cutting in late, or a steady drip of water into the car’s cabin from the aircon etc suggests a failing thermostat valve, icing inside the aircon from a leak and such.
When all this happens, it is an utter waste of time just topping up gas and hoping that will fix it. It won’t - the aircon is a sealed system so there is definitely a leak somewhere. Top the gas up mixed with a UV dye so that any leak will stand out and get located.
AudiWorld Stories
Bringing Audi to Life for Audi Fans
10 Strangest Audi Designs That Actually Made Production
Joe Kucinski
2027 Audi Q7 and SQ7: Audi Upgraded EVERYTHING!
Michael S. Palmer
Audi Unveils Absurdly Cool New Supercar: 10 Things You Need to Know!
Verdad Gallardo
The Highs & Lows of Every Audi C-Class Generation
Joe Kucinski
Top 10 Most Expensive Audis Ever Sold on Bring-A-Trailer
Brett Foote
10 Audi Features & Options We Miss the Most!
Joe Kucinski
Audi Recreates Crazy-Looking Speed Record Breaker From 1935
Verdad Gallardo
Coachbuilder Recreates the 1995 Audi TTS Concept
Verdad Gallardo
Every Audi V10 Car Ranked!
Joe Kucinski
Thread
Thread Starter
Forum
Replies
Last Post
Muhammad
Audi 100 / A6 (C4 Platform)
14
Apr 18, 2002 01:22 PM