Gas Mileage Drop after fuel filter??? | Ford Explorer - Ford Ranger Forums - Serious Explorations
  • Register Today It's free!

  • Holiday Special! - 2 for 1 Elite Explorer sale!

    Right now you can purchase an Elite Explorer membership for $20 and receive a two year membership!
    If you have an existing Elite membership contact me by PM and I will upgrade your account manually.

    Click Here to start your membership and get rid of the ads!

Gas Mileage Drop after fuel filter???

Ourobos

Member
Joined
September 4, 2007
Messages
44
Reaction score
0
City, State
Bowling Green, Kentucky
Year, Model & Trim Level
All Mustangs
I have an 02 v8 Eddie Bauer. When I bought the truck (used of course) I was seeing about 15 mpg around town and 18 mpg on the highway, combined roughly 16-17 mpg. Truck had ~ 140k on it. I was tickled with that. I'm pretty thorough about maintenance, so I wanted to make sure the truck was tuned up properly. First thing I did was replace the factory original looking fuel filter. Gas mileage went to crap, about 11 city and 13 highway. That is a big difference annually. So I replaced the plugs with some platinum ones. No change. I replaced the front two O2 sensors, BARELY an increase, maybe 1/2 mpg. I'm lost. Why would a new fuel filter KILL my gas mileage by 20% or more? Even better, what's a solution to get it back where it was? My air filter is new also BTW.

Thanks
 



Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!
.





Exproblems

Explorer Addict
Joined
April 17, 2011
Messages
1,684
Reaction score
12
City, State
Orchard Park, N.Y.
Year, Model & Trim Level
'05 Explorer XLT 4.0L
I . First thing I did was replace the factory original looking fuel filter. Gas mileage went to crap, about 11 city and 13 highway. That is a big difference annually. I'm lost. Why would a new fuel filter KILL my gas mileage by 20% or more? Even better, what's a solution to get it back where it was?
Thanks

Just a long shot here. Did you install the new fuel filter in the right direction? I know some aftermarket fuel filters have a "directional arrow" marked on the side of them showing which direction to install them in. The point of the arrow faces the engine and it relates to the flow of fuel through them from the gas tank to the engine.
 






Explorer0204

Well-Known Member
Joined
August 3, 2012
Messages
413
Reaction score
1
City, State
Upstate NY
Year, Model & Trim Level
04 Explorer XLT
Just a long shot here. Did you install the new fuel filter in the right direction? I know some aftermarket fuel filters have a "directional arrow" marked on the side of them showing which direction to install them in. The point of the arrow faces the engine and it relates to the flow of fuel through them from the gas tank to the engine.

Even the stock filter is directional I believe. Make sure to check this.
 






Ourobos

Member
Joined
September 4, 2007
Messages
44
Reaction score
0
City, State
Bowling Green, Kentucky
Year, Model & Trim Level
All Mustangs
Yes, It's installed with the arrow pointing toward the flow / engine direction.

Today I used some MAF cleaner and did the air box mod putting some 1" holes in the box to get more air into it. Still no change.
 






ponkotsu

Well-Known Member
Joined
October 29, 2012
Messages
620
Reaction score
7
City, State
Colorado Springs, CO
Year, Model & Trim Level
2005 Lincoln Aviator
I really doubt that you could worsen economy by replacing the fuel filter. A clogged filter would make the engine run poorly and almost always have increased fuel consumption, so changing it could only make it better. Probably just a coincidence, or maybe you did some other work at the same time? Don't just replace parts without being sure. Those parts cost more than the gasoline. Really tough to troubleshoot these without scanner data. If you have that you can see what the fuel trims are doing. If they are actually running rich, then you can dig further and figure out why.
 






Exproblems

Explorer Addict
Joined
April 17, 2011
Messages
1,684
Reaction score
12
City, State
Orchard Park, N.Y.
Year, Model & Trim Level
'05 Explorer XLT 4.0L
Yes, It's installed with the arrow pointing toward the flow / engine direction.

Today I used some MAF cleaner and did the air box mod putting some 1" holes in the box to get more air into it. Still no change.

You are good on the filter installation and I looked into doing the air box mod a year or so ago and from most of the posts I read on people who did it, most said it just made their vehicle sound louder, but no real gains on MPG's. So I didn't do it.
If this makes you feel better, I have a new, remanufactured 4.0L V-6 engine in my EX, little over 1k in miles on it and I'm getting around 1-2 MPG's less than my original motor got. The new motor came with new plugs, I had a new fuel filter installed with it and had Castle Fireball fuel injector cleaner added to the gas tank and my gas mileage sucks in this thing, especially if you sit and idle in the vehicle for any length of time. According to KBB's web site, my Ex is rated for 13-17 MPG and I get 2-4 MPG less than that on average, depending on whether I am doing city or Thruway driving. 2 1/2 years or so prior to the new engine install and right after I bought my Ex in Jan. 2011, I had all new tune up parts installed, plugs, wires, fuel filter, professional fuel injector cleaning at a Ford dealership, serpentine belt, engine diagnostic work done (no problems found) and never a CEL) and nothing helped me get any more MPG's out of this thing. So I have come to the understanding that "it is, what it is", a pig! The size of the rear diff gears could be part of the problem. Mine are the smaller 3.55 open diff gears.
I agree with what "Ponkotsu" said to you, don't throw money away on changing parts unless those parts really do need a change.
 






Ourobos

Member
Joined
September 4, 2007
Messages
44
Reaction score
0
City, State
Bowling Green, Kentucky
Year, Model & Trim Level
All Mustangs
It wouldn't bother me if I wasn't getting 15/17 at least, and now have dropped 4 mpg. And it happened immediately after the fuel filter change, so I don't know how it could be a coincidence. Once other thing I wondered, I used platinum plugs, is that was was original in these 4.6s, or were copper what Ford put in them? I know the platinum plugs have caused me and other many issues on small block Fords, I had always felt they were designed for the smaller 4 cyl. and 6 cyl. engines in the back of my head. Thanks for the responses though guys, I think I will wait on the ECT sensor, don't really think that's it.
 






jeff4912

Active Member
Joined
July 27, 2006
Messages
94
Reaction score
1
City, State
Seattle, Wa
Year, Model & Trim Level
2003 Ford Explorer 4WD
Any chance it's coincides with winter blend fuel which reduces gas mileage?
 






Ourobos

Member
Joined
September 4, 2007
Messages
44
Reaction score
0
City, State
Bowling Green, Kentucky
Year, Model & Trim Level
All Mustangs
It's been doing it since this past spring when I changed the filter. Good thought, but I'm in KY not CA, there's no winter blend here so to speak.
 






Exproblems

Explorer Addict
Joined
April 17, 2011
Messages
1,684
Reaction score
12
City, State
Orchard Park, N.Y.
Year, Model & Trim Level
'05 Explorer XLT 4.0L
It wouldn't bother me if I wasn't getting 15/17 at least, and now have dropped 4 mpg. And it happened immediately after the fuel filter change, so I don't know how it could be a coincidence. Once other thing I wondered, I used platinum plugs, is that was was original in these 4.6s, or were copper what Ford put in them? I know the platinum plugs have caused me and other many issues on small block Fords, I had always felt they were designed for the smaller 4 cyl. and 6 cyl. engines in the back of my head. Thanks for the responses though guys, I think I will wait on the ECT sensor, don't really think that's it.

The KBB mileage rating for my EX, 13-17 MPG isn't nearly what I actually get. I get 10-11 MPG in the city as long as I don't do much idling or warming the Ex up and on the Thruway at 65MPH or so, I get around 13-14 MPG. Not good at all.
On what spark plugs to use in the 4.6L you have, can't tell you because I have the 4.0L V-6. Most in here will tell you to use the OE Ford spark plug recommended for your engine.
 






Ourobos

Member
Joined
September 4, 2007
Messages
44
Reaction score
0
City, State
Bowling Green, Kentucky
Year, Model & Trim Level
All Mustangs
Thin is I'm going by actual mpg I was getting, not kbb rating.
 






Number4

"I'm counting to 3, then I'm getting your dad."
Elite Explorer
Joined
March 16, 2013
Messages
4,211
Reaction score
207
City, State
Woodstock, GA
Year, Model & Trim Level
04 Ford Explorer 4.6l
Is the vehicle running okay otherwise. ie no wanting to die at stops, or rough idle?
 






esclamada

Well-Known Member
Joined
October 25, 2010
Messages
502
Reaction score
1
City, State
KCMO
Year, Model & Trim Level
'02 Mountaineer AWD V8
Yes, It's installed with the arrow pointing toward the flow / engine direction.

Today I used some MAF cleaner and did the air box mod putting some 1" holes in the box to get more air into it. Still no change.

I don't really believe this air box mod crap. What it does is make the hot air on your engine bay go into your air intake because of those holes during idle. It does make a sound but that's it. Even if you replace it with a K&N filter (or similar) you need a heatshield at least.


How many miles since you've driven it after you disconnected the battery? it might take several miles for it to adjust.


-----------------------------------------------------------
MY MOUNTY
http://www.facebook.com/diyfordexplorer/photos_albums
 






Exproblems

Explorer Addict
Joined
April 17, 2011
Messages
1,684
Reaction score
12
City, State
Orchard Park, N.Y.
Year, Model & Trim Level
'05 Explorer XLT 4.0L
Thin is I'm going by actual mpg I was getting, not kbb rating.

So was I! I was trying to show you the difference between what I actually get in mileage versus what the vehicle was rated for.
 






Exproblems

Explorer Addict
Joined
April 17, 2011
Messages
1,684
Reaction score
12
City, State
Orchard Park, N.Y.
Year, Model & Trim Level
'05 Explorer XLT 4.0L
I don't really believe this air box mod crap. What it does is make the hot air on your engine bay go into your air intake because of those holes during idle. It does make a sound but that's it.

]

I agree with this ^ as well, because it makes sense. What surprised me about the air box intake nozzle was that it connects thru the front radiator support wall thru a cut out hole, only to have the back of the passenger side headlight and wire harness blocking up much of the air flow thru the hole to the nozzle inlet. Doesn't seem like great engineering to get proper air flow into the engine. Too many things in the way.
 






Ourobos

Member
Joined
September 4, 2007
Messages
44
Reaction score
0
City, State
Bowling Green, Kentucky
Year, Model & Trim Level
All Mustangs
The airbox mod makes perfect sense, the inlet on the bottom of the box is like breathing through a straw. You put the holes in the front side of the box where the same holes are the normal inlet runs through. You wouldn't want to put holes on the fan / engine side. Whether or not it helps with airflow, I can't honestly say.

I've only put a few miles on the truck since cleaning maf bit I'm looking at 12.1 mpg while I just pulled into this parking lot. I have a 10 hour trip coming up this weekend so that could be the tell of the tape, but overall since filter thousands of miles.
 






intelisevil

Well-Known Member
Joined
May 11, 2006
Messages
324
Reaction score
2
City, State
Sandy, OR
Year, Model & Trim Level
'00XLT-SOHC,'99Mounty-5.0
I'm looking at 12.1 mpg while I just pulled into this parking lot.

Are you trusting the message center for your mpg or are you doing the math through a series of fill ups?

Dan
 






Ourobos

Member
Joined
September 4, 2007
Messages
44
Reaction score
0
City, State
Bowling Green, Kentucky
Year, Model & Trim Level
All Mustangs
I do the math.. But currently I've went 120 miles on this tank, and it's over half gone..
 






Number4

"I'm counting to 3, then I'm getting your dad."
Elite Explorer
Joined
March 16, 2013
Messages
4,211
Reaction score
207
City, State
Woodstock, GA
Year, Model & Trim Level
04 Ford Explorer 4.6l
Did you disconnect the Battery when you did the filter? I don't see you saying how the ex is running otherwise.
 



Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!
.





Ourobos

Member
Joined
September 4, 2007
Messages
44
Reaction score
0
City, State
Bowling Green, Kentucky
Year, Model & Trim Level
All Mustangs
It's always ran great, even before the fuel filter change and mileage drop. I have had to replace timing chains, a COP, and the 4x4CM module, but don't think those are related to the EFI issue.
 






Top