Things to do to increase MPG

[ptf18]

Fellows: I posted previously about changing out the 3 O2 sensors in an attempt to get better mpg in the wife's '02 4.0l 2wd S/T.

She's refuel 2x since I changed the 3 sensors and much to my dismay the mpg hasn't "noticeably" improved. She's getting 17 to 18 mpg. I felt certain that the S/T was getting around 22ish or so but after I reviewed the mpg log book we keep I see that even years ago she was only getting 18ish mpg. On one vacation trip we did manage to get 22 mpg.

I would like to get ANY input about improving the MPG with this S/T. She drives very reasonable. Slow to accelerate and easy on the brakes. Her highway driving is usually done around the 60 - 65mph range. She is a grandma.

I check the T.P. every 4-5 weeks. Front at 32 Rear at 35. Brakes are not dragging. I stay atop of the maintenance per the Ford Owners Manual. She has 228k on the odometer. ( 95k on this engine as it was replaced by Ford...timing chain)

Motorcraft Plugs (SP500) have 8k on them

Motorcraft Plug wires have 24k on them

Motorcraft Air Filter has 19k on it

Motorcraft Fuel Filter has 19k on it.

I've never cleaned the injectors as I don't believe pouring 14-16 oz of liquid "cure" can do much in 20 gallons of fuel. Although I use to use RXP at every oil change. I believe that the only way to clean injectors would be to pull them and clean them. Thoughts?

I've cleaned the MAP / MAF (?) sensors with the correct cleaner about 5k ago.

I ran a ScanTool on the S/T after I installed the new O2 sensors. Took graft readings on the Fuel Trims. Don't have a clue what that info is telling me. It did change from the old sensors though.

I'm wondering about the 10% ethanol gasoline we are using. She purchases it from different stations. I told her to try Premium now that gas prices have dropped. Just to see if anything changes.

Any thoughts would be appreciated . Maybe its just the way it is but I would like to "get" 20+ if possible.

 

[Paul Fithian]

I typically see 16-18 MPG on mine, around town and 77 MPH on the highway.. New plugs and wires since 2016, doesn't smoke or burn oil. Not sure these get any better fuel economy in real world driving conditions.

 

[donalds]

It's needs a blower lol

 

[kmartin]

I doubt you will be able to increase it more. Its pretty much what they do when running good. Sure, you might get better running straight gas, where I live, straight gas is much more that it wouldn't pay for itself. Premium gas is only worth it, if your vehicle's computer can adjust for it.

 

[koda2000]

I don't think you will be able to do much better that 17-18 MPG on your ST. That's what I get on my Sport Trac w/4:10 gears. My 5.0's with 3:73's regularly get over 20 MPG highway (an all time high was 23.x) but around town 16-17 sometimes 18 is fairly normal (rural). My AWD did slightly less. I'm assuming you have 4:10's in your ST (which is pretty common). 4:10's make the SOHC V6 about as quick as the 5.0 V8, but not great on fuel economy. Paying for 100% gasoline premium would be a complete waste of money. The engine doesn't need it and it's way more expensive than 10% ethanol regular, which where I live is $1.97 a gal right now. I don't even think about my ST's MPG. When the needle gets to 1/4 I just fill it up.

 

[429CJ-3X2]

My '02 gets 15 to maybe 16 mixed driving/short trips in the summer. In winter the truck is generally just getting up to efficient operating temps on the drive to work, and I get 13.5 - 15. We several made trips from Des Moines to Kansas City and one to St Louis in the past year, interstate and 4 lane highways at 65-70 mph, and got 18-19. That's with 235/70/16 tires, 3.73 gears, topper, 2 adults, and more weight in the bed than necessary. I got 20 mph on a 125 mile trip at 65 a few years ago, before the topper, and without cruise control.

 

[ptf18]

Thanks Fellows. I guess I was just "thinking" the S/T got better MPG than it currently does. Oh well. Its been payed for for 14 years. Still cheaper to operate than what a replacement (new) would cost me.

 

[Sport100]

Find a garage with a Complete MotorVac Fuel System Cleaning Centre Machine. This is the best investmrent you can make when it comes to fuel milage. Cost about $100.00 here Canada. Uses a machine to clean fuel system, injectors, valves etc. I have used it for years best investment in Maintenance of complete fuel system. For five years I average 8 to 10 Litres per 100KM think that is about 33 to 24 MPG.Highway at 100KM per hour. Trips average 1800KM one way. But you must be on top of vehicle maintenance at all times. If everything is OK maintenance wish and milage falls off the first thing I do is go for Motorvac. See motor vac.com No I don't own shares or work for them.

 

[koda2000]

For five years I average 8 to 10 Litres per 100KM think that is about 33 to 24 MPG Highway at 100KM per hour.

I think I have to call BS on that mileage. I don't see a brand new '01 ST getting that kind of mileage and neither did the Ford or the EPA.

 

[hondaslave1342]

For five years I average 8 to 10 Litres per 100KM think that is about 33 to 24 MPG Highway at 100KM per hour.

I think I have to call BS on that mileage. I don't see a brand new '01 ST getting that kind of mileage and neither did the Ford or the EPA.

True..we barley get 18 mpg and thats adult driven...

 

[oklagp1200r]

If I drive 60mph best I got was 21mpg on highway with a 01 4x4 and i have a fiberglass lid on back!!

 

[Sport100]

I have been driving for over 70 years (over 3 Million miles) and have a complete set of logs for any vehicle I have ever driven, even client vehicles, be it auto, truck, transport, highway coaches or construction equipment, etc.. I have set proceedure I go thru before I get in the vehicle the first and every time. If its a long trip, more than 100km, more is involved. I was trained by and trained the industries best professionals from a very young age.

I have a couple of ?s- what oils and fluids do you use and how often is it check or changed? tire pressure how often do you check it? brake adjustment how often do you check it?your alignment and wheel balance how often do you have it check, after that hard bump, pot hole or hit that curb? and when you go on a long trip do you just drive or do a complete vehicle check before? Is that box open or covered? windows open or closed? I could go on and on all effect your milage and as far a EPA etc need I comment. I think I am an adult driver, opps maybe I should ask my wife.

I am gone.....

 

[cz413]

I average 15mpg if I remember correctly. I do speed a bit though

I've been thinking about removing or lowering the tailgate to see if it helps any. I don't have the factory tonneau cover

Mythbusters tested tailgate up or down. I believe tailgate down made a significant difference.