Can anyone get into a 03 Ford Explorer PCM??

[Racprops]

On the subject of MPG and how I believe the automakers are putting in a united BS Fix and I believe most cars could get better MPG: much like how the light bulb makers united in 1925 and decreed all light bulbs will ONLY last 1000 Hours.

About 12/14 years ago at the last gas crunch a friend, Don and I got into trying to improve MPG by installing a HHO system made by a company named Dutchman Enterprises.

It turned out to be a scam. But we did have a couple of success.

After we gave up on Dutchman with SO many believing in HHO I keep on researching and testing other systems nothing worked BUT two things:

Driving a V8 a (Ford 4.6) at 1500 to 1700 RPMs. These RPMs seem to be the SWEET SPOT.

And running lean burns at 16.4 A/R, which added about 5MPG.

Road tests was greatly helped by two MPG read out devices , a Scan GuageII and MPGunio. Which show instant readouts to no 100mile test runs were needed.

Test track is I17 North from Cactus to just past the 101 and south back to Cactus

Two runs each way. No wind.

Cars I have tested this on: a 2000 Mercury Grand Marques with a 4.6 4R70 4 speed auto and a 3.27 rear end that got 28 to 30MPG at 65MPH and 1700RPMs, and on a road trip from Phoenix AZ to Riverside CA got a nice 24MPG at 85MPH to the AZ/CA Boarder and then got 26MPG from the AZ/CA boarder to Riverside at 80MPH. MPG checked by numbers (at fuel pump fill ups) and two MPG devices.

This car would do these numbers every time every day!!

It was replaced by a 2003 Ford Crown Vic with a 4.6 4R70 4 speed auto and a 3.27 rear end that gets 26MPG at 65MPH P71 Ex-Cop car which makes 40 more HP over the 2000 4.6.

These two CARS show a normal progressive loss of MPG at a rate of about 3 MPG per each 5 MPH faster from 60MPH, no sudden drop in MPG just a steady drop as speed (and RPMS) increases.

BUT then there are these two Ford Explorers SUVs.

2002 Ford Explorer with a 4.0 V6 5R55 5 speed and 3.55 Rearend. Read end ratio is lower tht the stated 3.73 due to TALL wheels.

2003 Ford Explorer with a 4.6 V8 5R55 5 speed and 3.55 Rearend.

60MPH and 70MPH TRUE by GPS. I was concerned when the calculator program was off.

49MPH in 5th @ 1480RPMs 29MPG
59MPH in 5th @ 1800RPMs 26MPG

65MPH in 5^th @ 2200RPMs 18MPG

NOTE THIS DRAMATIC drop of almost 10MPG with only a small change in speed and RPMs

75MPH and up to 80MPH done nearly everyday. Everyone drives these speeds...

Note, from 50MPH and 29MPG to 65MPG the rate drops faster than the normal 1MPG per each 5MPH faster….should have been only 3 MPG to go from 50MPH to 65MPH what should be 26MPG reads 18MPG.

I have tested these low speeds of 50MPH about 8 times. On the freeways it takes a few second for it to settle down and then 28/32MPG. Note these MPG ONLY happen when cruising at a set speed.

This should not happen, you should lose MPG at a steady rate from 1500RPMs (50MPH) up.

BUT these two SUVs drop 10MPG between 50MPH and 65MPH THEN lose at the normal rate of 3MPG for each 5MPH faster.

So at 50MPH = 28/32, at 65MPH = 18MPG, and at 80MPH = 15MPG.

THEY say it is because these SUVs are Boxes being pushed through the air.

SO as a test I pulled up behind a Big Rig going north going a very nice steady 65MPH on I17, got within the vacuum behind his box, within one car space….and no change, no 29MPG just 18MPG.

So IT IS NOT wind resistance I was drafting the big rig.

And Because a 2019 Chevy Express van (A BIGGER BOX) is officially reported by its sticker to do 29MPG highway.

The FIX is in the PCM.

So I believe these PCMs can be reprogramed more like a Crown Vic programing and get much better MPG highway.

I am looking for help in doing this.

Rich

PS posted this again as I think it was in the wrong place.

[steveo]

here are my thoughts

fuel economy is produced by, for a particular load and engine speed, increasing power AND/OR decreasing fuel input.

engines are restricted by emissions laws at light loads. this does leave fuel economy on the table. often running leaner under light loads improves fuel economy, but it also can totally screw your emissions up. engines calibrated for countries that still use leaded gasoline often have no o2 sensors, and the cruise range tuned incredibly lean. on my "offroad only vehicles" with no cat or emissions testing involved i run a very lean mixture during light throttle.

at higher throttle and loads, stock calibrations have to be a bit rich for safety due to inconsistent fuel and potentially inaccurate feedback. tuning an engine to its peak power AFR can definitely help economy.

advanced engine designs are better at improving fuel economy than just tuning an old engine design, though.

variable cam timing can increase efficiency over a broader range (for example my 2 litre subaru engine with all four cams under closed loop control has a torque curve shaped like a chimney brick) that's why nearly all modern engines use it

direct injection is exceptional at economy, it allows precise control over air and fuel timing throughout the intake and compression strokes, not just blasting a bulk amount of fuel at the intake valve during the intake stroke. this allows fuel to be injected right before the spark event when the valve is fully closed, preventing detonation even under lean mixtures and advanced spark. direct injection engines can make amazing power with incredibly lean fuel ratios. that's why most engines making really good MPG numbers use it.

neural networks in modern ECMs can do advanced closed loop control using cam timing, fuel injection events, and other feedbacks to improve engine efficiency, in a way which can not be explained in this thread, which is why nearly all modern engines use it.

weight, rolling friction, and aerodynamics are very underrated in terms of their effect on fuel economy.

oh and how about cylinder disable systems? lots of those around. those help too. a V8 that becomes a V4 when it doesn't need to be a V8 definitely achieves better economy

so imo the fix to achieve peak fuel economy in a gas engine goes way way beyond the computer

[MO LS Noobie]

here are my thoughts

fuel economy is produced by, for a particular load and engine speed, increasing power AND/OR decreasing fuel input.

engines are restricted by emissions laws at light loads. this does leave fuel economy on the table. often running leaner under light loads improves fuel economy, but it also can totally screw your emissions up. engines calibrated for countries that still use leaded gasoline often have no o2 sensors, and the cruise range tuned incredibly lean. on my "offroad only vehicles" with no cat or emissions testing involved i run a very lean mixture during light throttle.

at higher throttle and loads, stock calibrations have to be a bit rich for safety due to inconsistent fuel and potentially inaccurate feedback. tuning an engine to its peak power AFR can definitely help economy.

advanced engine designs are better at improving fuel economy than just tuning an old engine design, though.

variable cam timing can increase efficiency over a broader range (for example my 2 litre subaru engine with all four cams under closed loop control has a torque curve shaped like a chimney brick) that's why nearly all modern engines use it

direct injection is exceptional at economy, it allows precise control over air and fuel timing throughout the intake and compression strokes, not just blasting a bulk amount of fuel at the intake valve during the intake stroke. this allows fuel to be injected right before the spark event when the valve is fully closed, preventing detonation even under lean mixtures and advanced spark. direct injection engines can make amazing power with incredibly lean fuel ratios. that's why most engines making really good MPG numbers use it.

neural networks in modern ECMs can do advanced closed loop control using cam timing, fuel injection events, and other feedbacks to improve engine efficiency, in a way which can not be explained in this thread, which is why nearly all modern engines use it.

weight, rolling friction, and aerodynamics are very underrated in terms of their effect on fuel economy.

oh and how about cylinder disable systems? lots of those around. those help too. a V8 that becomes a V4 when it doesn't need to be a V8 definitely achieves better economy

so imo the fix to achieve peak fuel economy in a gas engine goes way way beyond the computer

Thank you SteveO for the well thought out and explained modern engine dynamics overview. They are not your father's Oldsmobiles anymore. The only real reason to stay away from modern technology is for simplicity and cost. A simple deep dive on engine oils for these current engines will explain the complicated aspects of cleaning, cooling, and lubrication that something as simple as motor oil that has to be taken into account.
I am a big fan of the 2000 – 2007 LS engine family because for me it is the perfect compromise between simplicity and technology. My brother on the other hand still runs a big block with a carburetor. To each his own, but because I prefer an apple doesn't mean that you are wrong choosing an orange.

[Racprops]

Please reread this, I am only concerned with freeway driving and how I see a cheating program cutting MPG unneeded and unreasonable:

You missed the main points:

HOW A SUV can lose 10MPG going from 50MPH to 65MPH:

49MPH in 5th @ 1480RPMs 29MPG

65MPH in 5th @ 2200RPMs 18MPG

NOTE THIS DRAMATIC drop of almost 10MPG with only a small change in speed and RPMs

I have tested this on a 2000 Mercury Grand Marques with a 4.6 4R70 4 speed auto and a 3.27 rear end that got 30MPG at 65MPH and 1700RPMs!!!

So on a road trip from Phoenix AZ to Riverside CA got a nice 24MPG at 85MPH to the AZ/CA Boarder and then got 26MPG from the AZ/CA boarder to Riverside at 80MPH. MPG checked by numbers (at fuel pump fill ups) and two MPG devices.

SO here is the rate changes in MPG @MPH 1.25 MPG per each 5 MPH faster.

30MPG @ 65MPH +5 = 70,+5 = 75, +5 = 80 so the rate of Change is 1.25 per gal.

26MPG @ 80MPH +5 = 85MPH =24MPG so the rate of Change is 2 per gal.

All my cars,a 2000 Mercury, a 03 Crown Vic and a 2000 Toyota have a similar rate of change…

BUT these damn Explorers, and my 93 Chevy Van.


The Mercury was replaced by a 2003 Ford Crown Vic with a 4.6 4R70 4 speed auto and a 3.27 rear end that gets 26MPG at 65MPH P71 Ex-Cop car which makes 40 more HP over the 200HP 2000 4.6.

These two CARS show a normal progressive loss of MPG at a rate of about 1.25 MPG per each 5 MPH faster from 60MPH, no sudden drop in MPG just a steady drop as speed (and RPMS) increases.

I have tested these low speeds of 50MPH about 8 times on both Explorers.

On the freeways it takes a few second for it to settle down and then 28/32MPG at 50MPH and 1500RPMS. Note these MPG ONLY happen when cruising at a set speed.

BOTH of these SUVs going from 50MPH and 29MPG to 65MPG the rate drops faster than the normal 1.25MPG per each 5MPH faster….should have been only 3.75 MPG to go from 50MPH to 65MPH that should be 26.25 MPG BUT reads 18MPG!!!

This should not happen, you should lose MPG at a steady rate from 1500RPMs (50MPH) up.

BUT these two SUVs drop 10MPG between 50MPH and 65MPH THEN lose at the NORMAL RATE of 1.25 MPG for each 5MPH faster.

So at 50MPH = 28/32, at 65MPH = 18MPG, and at 80MPH = 15MPG.

65+5 = 70 16.7MPG +5 = 75MPH 15.5 MPG and lastly +5 =80MPH should show 14.25MPG, which I do see close to those numbers.

NOW if we skip the 10MPG drop: These two SUVs should show MPG like this.

50MPH @30MPG +5 = 55MPH @ 28.75 then +5 = 60MPH @ 27.5 now +5 =65MPH @ 26.25MPG +5=70MPH@ 25MPG and +5 = 75MPH @23.75MPG and lastly +5=80MPH@ 22.5 MPG.

THEY say it is because these SUVs are Boxes being pushed through the air.

SO as a test I pulled up behind a Big Rig going north going a very nice steady 65MPH on I17, got within the vacuum behind his box, within one car space….and no change, no 29MPG just 18MPG.

So IT IS NOT wind resistance as I was drafting the big rig.

Nor is wright, as I am maintaining a steady speed.

Now this will not be a BIG saving, but the fact that there seems to be a program robbing me of reasonable and normal loss of MPG as speed is increased bugs the hell out of me.

Rich

[MO LS Noobie]

Good luck with your adventure. Remember air resistance increases at the square of speed.

[Racprops]

Good luck with your adventure. Remember air resistance increases at the square of speed.

Note drafting a Big Rig, in his vacuum, no change....

Rich

[1project2many]

Also, OEM has to warranty the original catalytic converter for a *very* long time. And the vehicles still have to meet Federal fuel economy standards. It's a complex set of restrictions.

As steveo says, these systems are tied together in sometimes unexpected ways. I tracked fuel economy in a fleet of short buses for over 12 years. The 6.0 liter engine + 6L90E combination used until about 2018 averaged 2-3 mpg less than the previous TBI 5.7 plus 4L80E. It was a pretty drastic change. At one point I experimented with locking the converter in 4th - 6th gears to improve transmission durability. The bus transmissions stopped burning up and as an unexpected benefit, fuel economy increased.


The challenge in this thread is that the reporting is highly subjective, and rather than seek more data as to why OP has concluded that the automakers are creating calibrations that waste fuel. Strange, when another long term member of this forum has talked about achieving incredible fuel economy with the same type of vehicle.

[Racprops]

Also, OEM has to warranty the original catalytic converter for a *very* long time. And the vehicles still have to meet Federal fuel economy standards. It's a complex set of restrictions.

As steveo says, these systems are tied together in sometimes unexpected ways. I tracked fuel economy in a fleet of short buses for over 12 years. The 6.0 liter engine + 6L90E combination used until about 2018 averaged 2-3 mpg less than the previous TBI 5.7 plus 4L80E. It was a pretty drastic change. At one point I experimented with locking the converter in 4th - 6th gears to improve transmission durability. The bus transmissions stopped burning up and as an unexpected benefit, fuel economy increased.


The challenge in this thread is that the reporting is highly subjective, and rather than seek more data as to why OP has concluded that the automakers are creating calibrations that waste fuel. Strange, when another long term member of this forum has talked about achieving incredible fuel economy with the same type of vehicle.

Please tell me how to find him.

Rich