[mscribellito]

so ive been getting terrible gas mileage since october now. i dont know the exact mileage because my odometer gear broke and i havent replaced it yet. but its pretty bad. it seems to have gotten bad when i took the intake manifold off. but it is bolted down tight with a new gasked so i dont believe it is that. i replaced the throttle body gasket as well.

i change my oil regularly
recently changed tranny fluid
replaced fuel and air filter
cleaned maf wires
cleaned iac
my o2 sensors are good
i have mil eliminators
tire pressure is good
fuel pressure is withing range
and i ran some fuel injector cleaner
plugs and wires were replaced last year

i keep on pulling P1401 Differential Press Feedback EGR Circuit High Input
ive replaced the dpfe sensor and the valve was replaced a year ago as well as the evr. i dont think that would be causing the decrease in mileage because i had the egr problems before and it didnt seem to affect mileage.

im really stumped and have no clue what else it could be

[Trance]

has it been cold lately in your area?


i often see a hit in milage when the temps drop to near freezing.

[mscribellito]

i live in south carolina so it doesnt get too too cold here.
this is hard to explain but when im driving the car i cant really see the guage drop that much. its when i start it up next time i see that it went down considerably. idk if that makes any sense.

[mmvi]

intake manifold wouldn't have anything to do with it as far as I know... if it did, there'd be a vacuum leak, and you'd be dumping fuel into the exhaust. plus, your brakes wouldn't work as well as they usually do if it was a vac leak.

i keep on pulling P1401 Differential Press Feedback EGR Circuit High Input? -I don't understand that...

why'd you take the intake manifold off?

[mscribellito]

Originally Posted by mmvi i keep on pulling P1401 Differential Press Feedback EGR Circuit High Input? -I don't understand that...

cel is on and thats the code that comes up

Originally Posted by mmvi why'd you take the intake manifold off?

replace valve covers

[PowerShiftz02GT]

Possibly need a new fuel Filter. Just a guess though. You usally change them around 50000-60000 miles

[ESG-642T]

Originally Posted by mmvi intake manifold wouldn't have anything to do with it as far as I know... if it did, there'd be a vacuum leak, and you'd be dumping fuel into the exhaust. plus, your brakes wouldn't work as well as they usually do if it was a vac leak. i keep on pulling P1401 Differential Press Feedback EGR Circuit High Input? -I don't understand that... why'd you take the intake manifold off?

Depending on the leak you wouldn't notice it -
Any leak past that and you would notice your car sounding like it was cammed.

[mustangjeff1997]

yea, i noticed that my fuel guage likes to lie to me like that a lot too...it drives me insane because sometimes i'll pull into the garage with 1/4 tank and i'll leave the next morning with 1/8. it's a freakin' nazi, lol

[El_Cangri]

are you sure your really getting bad mpg?

you should get your odometer fix and check your mpg who know if its ur fuel gauge going bad

and even I dont understand that code lol

[mmvi]

Try this -explains the problem and how to fix it