Cabin temperature issues

cheechy

A2OC Donor
Looking to try and get ideas if I have an issue or not, and if so what could be causing the problem.

So just had a few things replaced and the mechanic has cc unit set at 28 degrees when I picked it up..very toasty. So immediately turned down to setting "lo" and the cabin was quickly filled with very hot air.

I gave the system a few minutes whilst driving and tried again with the same result.

Now I run obdeleven on it before and it flagged issues with ac...but even without that I would have hoped there would be some sort of temp regulation?

Incidentally I took a 30 min break and commenced journey and after initial blast of hot air it went down to cooler ( not cold) air.

I have an ac pump to go in just concerned there may well be something else going on...suggestions?
 
sounds more like a sticking / faulty flap motor on the climate control unit
Try giving it a good workout on the temp buttons, spend 15 mins cycling between hot and cold, this should free it up if it is simply sticking (Quite likely)
 
sounds more like a sticking / faulty flap motor on the climate control unit
Try giving it a good workout on the temp buttons, spend 15 mins cycling between hot and cold, this should free it up if it is simply sticking (Quite likely)

Good shout I think that's what the diags were telling me but I wrongly assumed it was the ac compressor!

If it is faulty can the motor be replaced do you know?
 
yes it is possible to replace the motor, never had a need to do one. It may need the dash removing to gain access, not 100% sure
 
I've had a similar issue on my 2005 TDi almost since new. It's a sticking valve in the internals of the heater matrix that stick on the default parked position of "hot". Mine was under warranty when the problem was found, but Audi did warn me that to fix the problem, the entire dash had to be removed in a 9-hour operation, and would be unlikely to go back together as well as the factory fit would be, so given it was intermittent did I really want to do it? It confuses the automatic air conditioning system if you have that fitted, in that it detects the car isn't cooling down fast enough, so it turns UP the fan so blows more hot air and the cycle repeats until I've had the car at seemingly 50+ degrees.

What I have found is that the "stickyness" of the value is improved by using air-con cleaners (the canisters of smoke type that you close in the car with re-circulate on). The other method I've noticed is allowing the valves to move from their "home" position when parked to "operate" before you finish turning the key to a cranking position. You'll hear a "whirr", followed by three small additional "whirrs". Waiting for those to finish before turning the key to "start" seems to cure it for me (perhaps the voltage drop on cranking leaves the valves without enough power to properly position themselves.

Hope that helps.
 
Ok wow thanks won't be getting this fixed on a hurry!
Would it help if I rolled my trouser leg up and counted to 500 backwards in elvish? :)

Cheers for feedback.
 
Scan does identify flap motor as intermittent. Seems to be ok to start and after a while (and in these temps) the cabin temp and heat rises. Turn the cc unit off and temp reduces again quickly.

I may have to get this fixed at some point but I might try regass first.
 
If the problem is a "sticking" temperature control flap motor it can be replaced without removing the dashboard. Its accessed after removing the glove box and very fiddly but it is possible.
 
a re gas will do nothing to fix a sticking / faulty control flap. I thought it was possible to replace the flap motor without removing the dash, thanks 'Special edition' for confirming this
 
For info, this is a schematic of the aircon system showing the relative position of the motorised flaps

Cheers Spike
 

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Hi,

the temperature flap motor is probably the easiest one to replace. Only the glove box has to be removed for access. An endoscope camera is required to re-align the gears afterwards though as they can't be seen directly. A small mirror and light on a stick might work as well.
http://www.a2oc.net/forum/showthrea...t-control-and-windscreen-demister-flap-motors

More info:
http://www.a2oc.net/forum/showthread.php?25089-Anatomy-of-the-A2-climate-unit

The only thing that could need replacing where the official Audi procedure requires the dash to be removed is the G263 Evaporator outlet temperature sender. This isn't easy to get to on RHD cars (although is very easy on LHD).
However, it is possible to replace from below with minimal dismantling:
http://www.a2oc.net/forum/showthrea...-temperature-sender-without-removing-the-dash

A scan of faults on the climate control unit will report what's wrong. The motors can suffer with electrical contact issues with the wiring inside the plastic casing. This often is intermittent with vibration which means that the motor can work fine when the car is stationary but develop a fault when the car is being driven. The control unit will disable the motor when it detects a fault although this is reset when turned off. This often means that the motor moves the flap into the initial position when the ignition is turned on but is then disabled once the car is being driven. If the weather is cool, given the thermostatic heat control, this can mean that the flap is moved to the full heat position and then stays there.
I haven't tried to break one apart and see if it can be fixed yet so the only solution at the moment is to buy a new one if faulty.

regards

Andrew
 
Great info. I'd probably want to get hold of one now as it's annoying. I've found in my case that the temperature send to stay stable unless you turn it down to much and then the cabin temperature starts to rise. It's like it can't cope.

Is there more than one type of v68 flap motor and if so what do I need for a 2004 1.4tdi 90?

Do I have more than one option I think is the question?
 
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Great info. I'd probably want to get hold of one now as it's annoying. I've found in my case that the temperature send to stay stable unless you turn it down to much and then the cabin temperature starts to rise. It's like it can't cope.

Is there more than one type of v68 flap motor and if so what do I need for a 2004 1.4tdi 90?

Do I have more than one option I think is the question?

Hi,

yes, there are two types and they aren't interchangeable as the mounting and electrical plug are different.

If your car is a 2004 then you probably have the later type. The changeover was on VIN 8Z-4-018 625.
The later type part number for the temperature motor is 6Q0 907 511 C. That part however isn't available any more new from Audi.
When I replaced the temperature motor in the thread quoted earlier, there was an alternative more generic part 6R0 907 511 available instead.
This generic part lacks the alignment aid "key" in the gear teeth.
I sourced the original like for like part as old unused stock from eBay.
Its also worth mentioning that the "6Q0" part is a VW Polo part originally.

regards

Andrew
 
So progress on this this far. AC compressor was definitely gone so was replaced. Car was then regassed.

I now get cool air still wouldn't say super cold but not really sure whether this is the norm in the A2. In my TT MK3 for instance or the wife's V40 those guys get much cooler.

The temp control flap still needs replaced as it's not playing ball either. However concerned that the air con isn't as cool as it should be in my opinion. The thermostat had been changed so what's left?

Sensor?

Or do I just replace the whole car? :)
 
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I would hope that a re gas would involve a "leak" test. Ive heard that a green dye is introduced into the system to highlight any escaping gases around the various pipe connections. :confused:
 
I would hope that a re gas would involve a "leak" test. Ive heard that a green dye is introduced into the system to highlight any escaping gases around the various pipe connections. :confused:

Yes and Tbh now had it regassed twice if I'm honest. Once before I got the AC compressor fine and once after. Before highlighted no leaks but a dead AC compressor.

Don't think they are allowed legally now to regass knowing there is a leak.
 
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G263 sensor (from memory), if this fails then the Aircon works in a kind of limp mode, cool but not cold
the sensor is located in the heater box in the middle of the car, official way to replace sensor is dash out, but there is a guide on here somewhere about doing it from the drivers side near the clutch pedal, but it is very tight for space
VAGCOM would likely show the G263 sensor as intermittent or implausible

cheers
 
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VAGCOM would likely show the G273 sensor as intermittent or implausible

Yes, it will. A scan with VCDS is essential. Ignore the intermittent only errors. The most likely source of a leak is the condenser, but might be just a failed O-ring. If the dryer is original, that should be replaced.

RAB
 
Yup think it's g263 sensor and I've already found a couple of good looking write ups in the archive.

The whole air con thing is doing my head in didn't realise how broken it was before I bought the car!
 
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