MPG issues on 2002 A4 1.9TDi Quattro

[Muiry8]

Hello,

Firstly sorry if this is in the worng place or a replicate of another thread!

I have had my Audi for 4 months now and was initially getting 50-52 mpg put of it working at roughly 650 miles from a tank which made me very happy (sold a petrol VRS for better economy). However in the past 3 weeks the economy has plumeted and I am struggling to get more than 500 miles out of the tank .

The car in this time has had a new turbo fitted and all round new tyres (michellin premacy hps were on but been replaced by hankooks). It had done some towing 4 weeks ago, 759KG dog trailer but was still returning 49 mpg when towing. Does anyone have any suggestions what could be the problem? The enegine temp is bang on 90 when up and running, it is due a major service and timing belt change as it has 72k on the clock.

Any advice would be greatly appreciated.

Thanks

[Doctle Odd]

Can you get it scanned, could be something as simple as dirty fuel/air filters or a MAF sensor.

[nevo]

Start by checking the simple things first,tyre pressures,check the hubs aren't getting hot,see if it freewheels for a reasonably distance,as above get it scanned,could be the coolant temp sensor,or the mass air meter as previously mentioned although it may not show as a fault code.