Irrespective of length of journey the cooling fan will run on for exactly 10 minutes when engine stopped. Also noticed that Start/Stop system not operating and also when aircon switch on warm air is blowing out. Local Audi dealer says no fault shown on diagnostics but this does not appear to be normal operating. 

The fan doing this could be part of the dpf regen. I'd recommend you get a second opinion 

Sorry I should have said the A4 is a 35TFSI

Stop/start not work can be a classic symptom of a failing battery.

I would suggest getting the battery efficiency check first - Halfords stores are usually capable of doing that.

Worth getting the alternator output checked at the same time.

It would be worth returning to the forum before committing to buy anything if anything is found to be substandard. 
Please let us know how you get on Charles.

Kind regards,

Gareth.

There is no issue with the car. Spoke to Audi who say it is normal and it’s the PPF Regenerative System. Probably cause by too many short runs. Same as the DPP on the diesel cars the newer petrol cars have the same regenerative process to burn off soot trapped in the exhaust system.

 

 

Glad it's nothing to worry about 🙂

18 hours ago, Charles Wheatley said:

 Spoke to Audi who say it is normal and it’s the PPF Regenerative System. 

I did not know until now that PPFs existed, but it seems they have been around for seven years. Thanks for informing me.

Regenerate the DPF and Have the EGR cleaned out aswell.

a large proportion of the time if your DPF is clogging up from shorter journeys, then your going to need to clean out the EGR Valve too.