Poor fuel economy

[Ryan Rønning]

I have a guy bringing a truck in to me today that is getting only about 12 to 13 MPG. It has 33' tires and no tunes. My truck has 37's and tunes and gets better then this. What would be some reasons other then a heavy right foot why his mileage sucks.

[AhrmanHammer]

Could have a fuel leak... may have some useful info in these threads.

poor fuel mileage

Filter drain o-ring leak or something else?

I'm having the same problem with my truck,11-13mpg on a basically stock truck even has stock tire size. I've been busy at work and its been too cold out to look into the problem. (Wish I had a garage)

Anyways, Good Luck finding his though...

[jesilvas]

Boost leak? (I'm assuming it's a diesel and turboed?)
Exhaust leak?
Weak fuel pump might do it? I can't remember what you're problem was but wasn't it a bad pump?
Fuel filter? Air filter? Oil filter and change? When were they done last?
Maybe some clogged fuel lines, injectors?
Heavy truck?
Bad gearing in the rear diff?
Low tire pressures?/Not correct pressures?
Wind resistance?
Thermostat won't open and running too cold?
Ok I'm tired of throwing stuff out there
That's all I could think of anyway.

[02stroker250]

Originally Posted by jesilvas

Boost leak? (I'm assuming it's a diesel and turboed?)
Exhaust leak?
Weak fuel pump might do it? I can't remember what you're problem was but wasn't it a bad pump?
Fuel filter? Air filter? Oil filter and change? When were they done last?
Maybe some clogged fuel lines, injectors?
Heavy truck?
Bad gearing in the rear diff?
Low tire pressures?/Not correct pressures?
Wind resistance?
Thermostat won't open and running too cold?
Ok I'm tired of throwing stuff out there
That's all I could think of anyway.

ah come on theres got to be one more in there somewhere

[jesilvas]

Oh yea. Dragging brake pads?

[Ozone-etr1]

Originally Posted by jesilvas

Boost leak? (I'm assuming it's a diesel and turboed?)
Exhaust leak?
Weak fuel pump might do it? I can't remember what you're problem was but wasn't it a bad pump?
Fuel filter? Air filter? Oil filter and change? When were they done last?
Maybe some clogged fuel lines, injectors?
Heavy truck?
Bad gearing in the rear diff?
Low tire pressures?/Not correct pressures?
Wind resistance?
Thermostat won't open and running too cold?
Ok I'm tired of throwing stuff out there
That's all I could think of anyway.

passenger seatbelt not engaged?
rear vent windows open?
didnt clean thr prius off the grill?
dragging part of a mail box you didnt see when backing up?
parashoot break engaged?? (could have a hemi)
DUNNO

[02stroker250]

Originally Posted by Ozone-etr1

didnt clean thr prius off the grill?
DUNNO

[Ryan Rønning]

Thats some good stuff. His OBD pord was busted so no code pulling. Having to do this old school

[dalton1]

Originally Posted by RRonning1984

Thats some good stuff. His OBD pord was busted so no code pulling. Having to do this old school

why dont you fix it :
computers are your friend

[JakeLewis79]

Might have a heavy right foot
might be letting it idle a lot to warm up
EBPV kills mileage/power
brake dragging