I've just bought a 2006 Panda Multijet. It replaced a Peugeot 106 1.5 Diesel. The peugeot was slightly bigger, a bit heavier, had an older design indirect injection mechanically controlled diesel, and was pretty worn out (which is why we sold it). But here in rural Wales it averaged around 70mpg (real figures, miles divided by gallons) and never did <65.

It was the second one we owned, they were both equally economical. The Panda ought to be more economical, but it feels less lively than the old Peugeot and so far it's only doing about 62mpg on the same routes with the same two drivers. It seems a pretty poor show that with all its computer-optimised engine management, and with direct injection (inherently more efficient), it uses more fuel to haul less weight around more slowly.

Is it possible for it to have an engine fault if no warning lights are on? It seems to run fine, but is much more gutless below about 2500rpm than the peugeot, and peak torque is supposed to be at 1500rpm, which is 1,000 rpm less than the 106 diesel.

Could we use our warranty (it came for a dealer) to get it checked out by an engine management buff?