Hi my 2005 1.9 tdi 4x4 octavia is giving very poor mpg returns.It's well serviced and it's a mixture of long runs and town driving. On a full tank i,m very lucky to get 400 miles. Any suggestions as to what the problem could be, thanks

5 hours ago, nuala said:

and town driving

First suspect. Mine wouldn't get past 45mpg on a 12 mile commute; It would easily do mid-50s driven faster on a 200 mile run though.

As Ken said. Engines take longer to warm up with town journeys (if at all) and lower outside temperatures.

 

You will also see a small improvement after the end of this month when fuel companies change over from winter diesel to summer diesel.

This is a transparent change that most drivers don't know happens. Here is a link for the change the other way.

https://www.fuelcardservices.com/bp-diesel-formulated-for-the-winter-months-ahead-2/

Many drivers private or commercial who have driven for winters over many years and decades know that Derv / Diesel does not give any lower MPG if there is warm weather during the months of October where the winter spec diesel is delivered first in Scotland and the north of England till April be that anyplace in the UK, lots of warm days / nights might happen during those months were the diesel vehicles do not need to travel further before the engine gets up to efficient temperatures. It is not as though the additive added then has the derv with a lower Cetane. 

 

Many do not know that the petrol also comes in Winter Formulations and that does not require more fuel to go the same distance if the weather is not actually that much colder than some spring, summer or autumn days / nights.

Edited 9 March, 20224 yr by roottoot

Check brakes for sticking, particularly the rear. Often overlooked.

Thanks for the help, turned out to be a brake caliper sticking.😮