• We’re currently investigating an issue related to the forum theme and styling that is impacting page layout and visual formatting. The problem has been identified, and we are actively working on a resolution. There is no impact to user data or functionality, this is strictly a front-end display issue. We’ll post an update once the fix has been deployed. Thanks for your patience while we get this sorted.

wth! my van's MPG went from 23 to 8.

waggy

waggy

No Lifer
ok as the title says my MPG on my windstar went from 23 (country driving) to 8 (again country driving).

sigh guess i should take it in. bah.
 
Fuel pump, spark plugs, air filter, fuel leak?

With that dramatic of a drop the vehicle should be running like crap. If it is running as it always has, I'd suspect a fuel leak somewhere.
 
JeffreyLebowski said:
Fuel pump, spark plugs, air filter, fuel leak?

With that dramatic of a drop the vehicle should be running like crap. If it is running as it always has, I'd suspect a fuel leak somewhere.
Click to expand...

that and also the brakes and wheel bearings. Make sure all wheels spin freely.
 
If there's no obvious noise, hesitation, or warning lights, my best guess for such a dramatic decrease is a puncture in the gas tank or fuel lines.
 
Hook up a scanner and check long term fuel trims, I ll bet they are maxed out on the + side and there will be a pending code for system too lean that hasn't lit up yet. Also no light could just mean a burned out MIL lamp, always check anyway.

Low transmission fluid and malfunctioning torque converter can also have a huge impact on mileage.
 
Last edited:
I had a timing belt failure one time where it didn't break, but it allowed to timing to change (and continually get worse). The car got very sluggish, and was wasting gas like crazy.
 
exdeath said:
Hook up a scanner and check long term fuel trims, I ll bet they are maxed out on the + side and there will be a pending code for system too lean that hasn't lit up yet. Also no light could just mean a burned out MIL lamp, always check anyway.

Low transmission fluid and malfunctioning torque converter can also have a huge impact on mileage.
Click to expand...

What would cause that? Dead/dying O2 sensor?
 
Sounds like someone siphoned your fuel tank, or you've got a leak somewhere (or the parking brake is on, lol). Bad sensors wouldn't bring it down 66%, and if it did, you'd have a CEL light and it would be running like absolute crap.
 
LTC8K6 said:
Maybe he put E85 in it...that'll kill your fuel economy by 25-30%
Click to expand...
No way in hell. Even if the ethanol had zero energy content, the decrease in fuel economy would be 15%, unless you're saying the ethanol has a negative effect on the overall system...?
 
Howard said:
No way in hell. Even if the ethanol had zero energy content, the decrease in fuel economy would be 15%, unless you're saying the ethanol has a negative effect on the overall system...?
Click to expand...

You might want to check your math there... E85 is 85% ethanol.

Ethanol has about 75700 btu/gal
Gasoline has about 115000 btu/gal

If you do a weighted average for an 85% ethanol/15% gasoline mix you end up with 81,595 btu/gal, a 29% drop in energy content/gallon.
 
Howard said:
No way in hell. Even if the ethanol had zero energy content, the decrease in fuel economy would be 15%, unless you're saying the ethanol has a negative effect on the overall system...?
Click to expand...

http://www.caranddriver.com/var/ezf...lication/04b8987d7b1d3ed794ea9a354dc9b755.pdf

From a 2011 Owner's manual:

Starting
The characteristics of E85 fuel make it unsuitable for use
when ambient temperatures fall below 0°F (-18°C). In the
range of 0°F (-18°C) to 32°F (0°C), you may experience an
increase in the time it takes for your engine to start, and
a deterioration in driveability (sags and/or hesitations)
until the engine is fully warmed up.

NOTE: Use of the engine block heater (if equipped) is
beneficial for E85 startability when the ambient temperature
is less than 32°F (0°C).

Cruising Range
Because E85 fuel contains less energy per gallon/liter
than gasoline, you will experience an increase in fuel
consumption. You can expect your miles per gallon
(mpg)/miles per liter and your driving range to decrease
by about 30%, compared to gasoline operation.
Click to expand...
 
waggy said:
ok as the title says my MPG on my windstar went from 23 (country driving) to 8 (again country driving).

sigh guess i should take it in. bah.
Click to expand...

my 2001 windstar is only getting us around 18 mpg now. used to get around 21-22 but I guess after 170k tolerances might not be as tight.

My 1994 ranger once got pretty bad gas mileage, but I think it was because the thermostat was running wide open all the time and never warming up the engine.
 
Last edited:
i checked the lines and no puncture in the tank.

bah guess i take it in. a few other people i talk to say the 02 sensor. hope its not expensive or hard to fix.

on a side not i forgot i even posted this. i was about to post this asking if it could be the 02 and how to fix it..sigh im getting old.
 
from what i been looking at the o2 sensor is a easy fix. just a matter of getting the right one.

i shall attempt it! ..if my van blows up ..well i love you guys!
 
You must log in or register to reply here.

TRENDING THREADS

Back
Top