Can a car spring a fuel leak!?

[themonke]

Alright guys so as some of you know i am currently driving a 1600 petrol fsi.
From recent calculations over a number tanks of fuel my car seems to be averaging around 25mpg!!

This figure consists of  long motorway runs and town driving combined!
Also my car is never driven hard or raced about!

initially i thought the car may need a service, although it is done yearly by the "stealers" however i still did a six monthly service and run the car through a couple more tanks of juice and still no joy 

Am i been a bit optimistic or is 25mpg wrong?

Has any one got any ideas as this is really starting to frustrate me, as petrol prices are forever rocketing and my car is drinking it like its going out of fashion!?

[FamilyDub]

Computers lie and also work in averages. The VW ECU is calibrated in km, so that might hurt it even more too.

Have you actually started recording how many litres, costs and mileage travelled on a sheet of paper? Try it...

Although for a comparison, I do two cold start journeys totalling no more 5 miles a day during the week. I give it a long, mixed driving run 'enthusiastically' at the weekend and I even still can't do any worse than 27-30mpg.

[Nasir]

Even if the computer is a bit off, that's seriously wrong. You should be seeing 35+ ideally, what fuel are you using? That's the biggest factor as most people don't understand the FSI needs high octane to work efficiently. There was a thread on this on Uk-mkivs.net and the guy had better MPG after putting in super. But it sounds like the cars using way too much fuel anyway, maybe a dodgy sensor? How does the car drive?

Heres the thread on uk-mkivs.net, look towards the end of the thread:
http://uk-mkivs.net/forums/t/332134.aspx

[themonke]

Thanks guys, as my car is a base model i have no trip computer so the calculations is just hard maths on my account lol.

I do however use 95ron fuel. i am due ANOTHER fill up tonight so will try the 98ron petrol.

The car seems to drive fine smooth and responsive (as responsive as you can get out of an 1600)

Thank for the link ill take a look