Why do i have poor mileage?

[zagarus]

well for some reason my mileage hasn't been what im thinking i can get.  I range from 34-40 mpg.  On the highway i got 42.5 one time, but usually it hovers around 36-38.  Any ideas what i could do to help it?

[Darkness_is_spreading]

Need to know more about the motor, mods,  age and condition of motor......

Also how you drive your car, will affect it......

[BlackTieTD]

Need to know more about the motor, mods,  age and condition of motor......

Also how you drive your car, will affect it......

...wheel bearings, dragging brakes, wheel alignment, tire inflation and some factors other than motor/driving style will also effect it.

[shwartzbewithyou]

Is it idling properly when it sits running?  Popped the hood for visual inspection yet?  Are the injectors dry?  When's the last time it had a tune-up?

LOTS more info needed.

[zagarus]

well for starters the fueling is turned up a bit, when warm i idle at 1100, tune up done a few weeks ago include new timing belt, alternator belt, coolant flush, and new water pump.  I try to drive efficiently, but the need to smoke people is always there.  Its a 1.6l TD with 260,000ish.  I guess just time and age makes it loosen up and not so efficient anymore.

[LeeG]

1.6l TD with 260,000ish. I guess just time and age makes it loosen up and not so efficient anymore.

Mine gets the same mileage now at 410,000km it did at 260,000km.  I was getting 48 mpg on a daily 240 km city/highway commute.  Now I am doing just city, 80 km daily and mileage looks like it might have dropped to 45-46, but havent run enough tanks to be sure.  Mine is plenty loose and I dont drive efficiently!  I would expect you to get better than 40 mpg unless you have a dead cylinder or something.  

Have you checked your timing?  Do you get much smoke since turning up fuel?  And the other stuff about brakes, alignment, bearings people have mentioned.