F250 power not what it should be

[SapoF250]

Hi,
I have a 2000 7.3 4x4 automatic with 180,000 miles on. a superchip tune from 2002.no other modifications to it.
for about the last year i noticed that my mileage has been slipping and it is needing to down shift to get up mild hills it used to pull up no problem in high gear. it isn't always consistent. part of a trip it will do this and not during the rest. temperature doesn't seem to affect it any.
anyone have any ideas? turbo vanes sticking? injectors bad? egr?
any help would be greatly appreciated.

[atvrider93]

well, you don't have turbo vanes.......or an EGR.....so it's not those. check the air filter and fuel filter first.

[SapoF250]

Thanks, the air and fuel filters are fresh. The oil is frequently changed also.
Also went through and checked/tightened all the clamps for the charged air hoses.
any other thoughts?
Tires are at correct pressure and transmission is recently serviced.
thanks. I'll take any ideas.

[jesilvas]

You have no egr or turbo vanes.
EBP sensor and tube, MAP sensor and tube, EBPV possibly sticking, exhaust leaks, boost leaks, fuel pressure low, ICP or IPR issues.

I made my Samsung SGH-I997 send this.

[kaya@bernhausen]

returning the tune to stock is always a good place to start

[SapoF250]

Ok thanks i will explore these possibilities as soon as i figure out what all the abbreviations are

[atvrider93]

How much exactly has your mileage gone down?

Sent from my DROID BIONIC against my will

[SapoF250]

Don't have an exact. Seems my low fuel light would come on at 330-350 miles and now it is more so 285-315.usually fills about 23 gallons at this point.
I try to be consistant with how i top off. Usually just going till it shuts off. I know i can trickle a lot more in but generally don't want to take the time. Same tires and no extra roof boxes or anything.
I was attributing the lower mileage to the fact that it's spending more time having to down shift to get up hills and such.but that's just a theory i have.