Hope you can help here. My 2005 Mondeo 3.0V6 used to do about 26mpg (last year on holiday, fully loaded with 600 kg trailer too) but now, according to the computer the mpg has dropped to 21.8 which is reduction of about 20%.
Although the car is no longer dealer serviced I do look after it myself and it does about 15000 miles a year for work.
Oil and filter are changed every 12000 miles and the car has a K&N filter which is serviced according to the
Realising that the plugs have probably been in the car from new (it has 36000 miles on it) I pulled out one of the front plugs and could have driven a truck through the gap so I changed all six (that was fun - if anybody needs any help with that job just get in touch....). No difference.
It has been suggested that a brake may be binding but all four wheels spin freely. It was also suggested that there may be a faulty lambda sensor (this car has 4) and that would seem to make sense.
What do you think?