Audi A4 1.9 Tdi - Continuous hot air from heater

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Thu 25 Feb 2021 11:53
Audi A4 1.9 Tdi - Continuous hot air from heater - Steveieb

My air con has broken on this car and I have been advised that the repair is so expensive on cars of this age 2003 that it simply isn’t worth it.

But the cabin temperature last summer was unbearable , but over the winter the heater would not work so I had the thermostat replaced.

Now the warm weather is arriving I am unable to turn the climate control low enough to establish a liveable temperature, .

Have you any advice please ?

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Thu 25 Feb 2021 13:35
Audi A4 1.9 Tdi - Continuous hot air from heater - elekie&a/c doctor
Check the air blend servo motors are working. You will probably need to remove the glove box and bits of under dash trim on driver side to check the flap linkages are moving . If these are ok , then as a cheap fix get yourself a pipe clamp and put it on one of the heater hoses . Access under the scuttle panel , by the battery .
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Thu 25 Feb 2021 14:21
Audi A4 1.9 Tdi - Continuous hot air from heater - Steveieb
Brilliant advice as usual Elekie doc.
Any idea what sort of pipe clamp would be best ?
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Thu 25 Feb 2021 19:04
Audi A4 1.9 Tdi - Continuous hot air from heater - elekie&a/c doctor
Laser tools #4976 should do the job.
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Sun 28 Feb 2021 16:43
Audi A4 1.9 Tdi - Continuous hot air from heater - Steveieb
Hi Elekie Doc.
Ordered the pipe clamp but wondered if it is possible to free up the flap somehow ?
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Sun 28 Feb 2021 16:53
Audi A4 1.9 Tdi - Continuous hot air from heater - skidpan

When this happened in the Puma I made a clamp out of 2 pieces of alloy and 2 bolts. I placed it under the bonnet just before the pipes disappeared through the bulkhead. Loosen the bolts to let a bit of warmth through, clamp them up to stop the heat.. Eventually I got a new valve and fitted it. This one eventually failed but instead of letting hot water through like the first the replacement failed in the shut position and let no heat through at all, a b***** when it failed in January. Refitted the original valve and clamp (just happened to keep them) and it was like that until I sold it.

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Sun 28 Feb 2021 19:03
Audi A4 1.9 Tdi - Continuous hot air from heater - elekie&a/c doctor

You need to establish if its actually a flap fault (or 2 flaps if it has dual zone climate). removal of the glovebox and under dash trims driver side will allow inspection of the servo motors and operating levers. if the servo motors have failed, then it is possible to move the mechanism by hand .Anything beyond this is dash out. Using a diagnostic tool like Vagcom/vcds should help with fault finding.

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