I have a 2007 Focus 1.6 TDCI 110 DPF with 89,000miles. Got it eight months ago when it had 82,000 and was fantastic until recently when I noticed a drop in mpg from around 45-50mpg to 35-40.

I live in a hot, humid climate and currently driving with the ac on almost all the time so I can understand a bit less mpg but 10mpg less? My older 2002 1.4 petrol Corolla only made a slight (less than 5mpg) difference when using the a/c.

I also noticed that its less powerful - feels much harder to rev - like carrying a ton of weight! Very hard to make a hill start as well. Another problem is that I noticed that there is less power steering assistance so when crawling the steering feels much heavier.