Why is my Peugeot 407 only getting 40mpg?
I am only getting 40mpg from a diesel Peugeot 407 on long trips; what can be the problem?Ken Power (Waterford)
It's difficult to know from afar, but there are several things that will affect this - assuming you're seeing a reduction in your car's economy:
1 - Tyre pressures need to be within specification
2 - Wheel alignment must be correct
3 - Perhaps the air filter and/or fuel filter is dirty and needs replacement
4 - Are you carrying extra weight in the boot?
5 - Is the rear window demister on permanently?
Go through all of those things, starting with those that cost nothing to check and you should find savings. If not, then get the engine are car serviced and that might help. Perhaps a brake is binding.
Let us know how you get onShane O' Donoghue - Complete Car Adviser