Air con problem on Audi TT

Wollyram

I have a 03 Audi tt, 1.8 with almost 38k on the clock and have recently noticed that if I switch the ignition on with the air con on I get a rumbling/shuddering from the engine. I have also noticed an unpleasant damp smell in the car when the air con is on.Anyone experience this?

biblio

Not familiar with the details of the TT but with car air con systems there are usually just a few common faults Re the damp smell , is the pollen filter clean,? it should be replaced regularly, there is a melt water drain in the bottom of the a/c unit with drain tubes that lead out under the floor these could be blocked causing a build up of water and eventually the damp smell check the carpet around the bottom of the dash to see if it is wet.
Also starting the engine with the air con on is not a good idea it causes a sudden load on the engine and a/c compressor to get maximum life from the system turn off ac before starting

Wollyram

Many thanks for the tips I will check the carpet etc., I did have the car serviced about three months ago but it's quite possible they didn't change the filter.:)