Hi, I have an 05 plate Octavia II 2.0 140PD and have recently had the cambelt changed, I also had the water pump changed at the same time. Anyway, since the work has been done I have noticed my avergae mpg (according to the onboard computer) has dropped however the car seems to run fine.

I got it done at the beginning of the winter so was unsure if the drop in temperature has brought the average mpg down, or if it could be something to do with the cambelt change.

My average mpg dropped in the summer so I changed the fuel filter which improved my mpg, that was about 4000 miles ago.

I have also inflated my tires as they were slightly deflated and the mpg improved slightly but it still isn't as good as what i was getting.

Any input would be much appreciated.

Has the air filter been changed recently? This would be the first thing to check.

Has the air filter been changed recently? This would be the first thing to check.

Yeah, I changed it at the same time as the fuel filter. The drop in mpg happened immediately after the cam belt/water pump change.