I have a 2004 A4 1.8T Multitronic with only 105k on the clock.

The aircon has always been great, cooling the car down fast even in 38°c weather. However, the last two years it does not seem to be able to cope anymore.

i took it to an aircon shop and they checked it out for leaks an regassed it, but there was no improvement. So I took it to my Audi dealer for a checkup. They said all was fine, but it is not.

in the past I would put the climate control to 21°c and it would automatically blow hard and flat out until the car was cool within a few minutes and then level off. It can now take 20-30 minutes to cool the car down. If I set the aircon to LO, it does cool down slightly faster. When I picked up the car from Audi they had left it at LO as well which is where I suppose they tested it at. But what is the point of having climate control when you have to adjust manually.?

My other car is a Mitsubishi Pajero. The Audi’s aircon always used to be much better, but now it’s not. What dan it be?

I have replaced the pollen filter and notice that the airflow seems to be unconstricted. It just not blowing cold enough air.
Is there perhaps an internal temperature sensor that is not working? Where is it. The dealership says there are no fault codes.

Any suggestions?