Probramed Bad MPG!!!???

[racprops]

I have spent a fair amount of time working on improving a cars MPG.

My current best car is a 03 Ford Explorer.

I love everything about it but its drinking problem…it is a bad drunk, it really drinks the juice.

And it is so out of line I believe Ford and other car makers are cheating us.

Comparing the MPG reading of the 03 Ford Explorer to other cars SHOWS THAT IT IS VERY ODD and Very off.

I am talking testing by pure nonstop runs at speed with crust control reading by a Scan Gauge II.

These test show what my cars CAN do on a road trip.

I had a 2000 Mercury Grand Marques, (A Crown Vic in Mercury trim) it GOT at:

65MPH 29/30MPG @ 1700RPMs, and at 75MPG got 26MPG and at 85MPH got 24 MPG.

Basically the same engine, only 40HP Less and a 3:27 rear end of my Crown Vic.

My 03 Crown Vic, gets at 65 26MPG @1700RPMs and at 75 MPH gets 22MPG. Again the same progressive loss of MPG per each 10MPH faster, it has 240HP, same transmission and rear end of the 2000 Mercury.

The 03 Explorer has the same 4.6 V8 as the 03 Crown Vic, even with the same specs of 240HP,
and with its taller wheels has a final gear ratio of 3:50 VS 3:27.

And yet at 50MPH @ 1500RPMs gets 27/32MPG…all very good…

BUT go to 60 MPG and 1800RPMs and it MPG drops like a rock to ONLY 18MPG, and it only drops a MPG for each 10MPH faster…

That is at around 55MPH the MPG DROPS to 18/19MPG, it has to be programed to do that…then for EACH 10MPH faster it THEN only drops 1MPG…

So once it has taken all the MPG away it then losses 1 MPG per 10MPH so even at 80MPH it still gets 16MPG.

EVERY Car I have tested this NOT normal!

Every CAR has the same progressive or slowly dropping MPG.

At 50 MPH you get a good MPG, and as you speed up the MPG SLOWLY drops, like the 2000 Mercury went from 32MPG at 50 MPH and for each 10MPH it dropped one or two MPG so 60 was 30MPG and 70 was 28 MPG and 80 was 26 MPG and 85 was 24/25MPG.

EVERY Truck, well SUV and Van I have tested has this odd fixed MPG readings.. A 02 Explorer, 03 Explorer: Go faster that 55MPH and BLAM 18/19MPG and my 93 Chevy Van also got only 14MPG at 65 to 85 MPH running a Van’s standard 3:43 rear end.

I rarely checked my 74 and 78 Chevy vans, but they with NO overdrive and a standard 3:43 rear end, running carbs got a similar progressive drop in MPG from 15/16 at 65MPH to mainly 13MPG at 75/80MPH.

So historically Vans and trucks got crappy MPG so the stage was/is set for modern Vans and SUVs to do so too…

We are told that a BOX cannot go through the air…

The 2003 Ford Explorer has a drag coefficient of .41 Cd.
The 2003 Ford Crown Vic has a drag coefficient of .37 Cd.

So it is easy to do a fix so that these newer FI computer controlled overdrive SUVs and Vans, and Trucks so that they will get their historically bad MPG.

I THINK IF I can find someone to program the fuel tables from say a 03 Crown Vic my/your Explorers will then get the same kind of MPG the Vic does.

So I am looking for a tuner to do this.


Rich

[Piotrsko]

Might be faster and easier to see if the obd system swaps. On the ranger, parts store indicate a series of years the computer interchanges, along with other models in the ford line.

[racprops]

Originally Posted by Piotrsko

Might be faster and easier to see if the obd system swaps. On the ranger, parts store indicate a series of years the computer interchanges, along with other models in the ford line.

I have been trying...problems are:

Finding a 03 car running a 4.6 with a 5R55s, only choices are the "New" T Bird and that is GOLD for those PCMs...like $600.00 up.

And the Lincoln Aviator, Damn it is a dressed up explorer with even worst MPG and as a SUV I bet has the same programing.

Next is the 05 up Mustang, which damn it like the 03 to 04 Ford Change the three PCM plug majorly.

Plus I am in PHX AZ and subject to smog testing and the PCM has to have the correct VIN number.

So I only can try to reprogram the PCM for the SUV, or try to figure out a interrupt like changing the O2 read outs, or the MAF IF it uses them to trigger the change or to compensate for the change.

Sadly that is only something I CAN do and it is not a fix for all the Fuel Injected trucks running a similar program, which I believe a lot of them do.

Like my 93 Chevy G20 Van which seems to get 14MPG no mater speed or up or down hills.

Rich

PS I cannot find any real world MPG pages, the https://www.fuelly.com/ ONLY gives the over all avg. Not city and highway...

I ONLY consider Highway of any worth, city can contain and LOT of stop and go and a lot of idling so it can be all over the Map.

My testing show what my cars CAN do on a road trip.

I want the best MPG for road trips where I will out in the country miles from my local gas station and on long trips feel the cost per mile mostly.

Knowing MPG can help plan fuel stops and being able to shop for best prices.

I have found normally on the road the better prices are in big cities and a couple of miles off the freeways.

[Piotrsko]

Fwiw in Reno diesel is +/- $6.00 @gallon. Gas, which I don't use I think is $5, maybe $4.75. Carson About 50¢ cheaper.

Same routine I'm going through with son and engine swap on a 88 4runner: computers won't match. There are however places online that can reprogram but the smog places are restricted to tail pipe emissions and seeing if the obd system reports READY/OK. serial number only makes the mechanic not have to find, copy and report the one on the dash.

All the computers I have come across prior to 2015 don't have embedded non changeable serial numbers, would fubar a non dealer repair shop doing a swap.

So I would go see if thats an actual requirement. I would also research spoofing various sensors: fuel pressure, O2 pre cat, TPS, rpm what have you

[racprops]

Originally Posted by Piotrsko

Fwiw in Reno diesel is +/- $6.00 @gallon. Gas, which I don't use I think is $5, maybe $4.75. Carson About 50¢ cheaper.

Same routine I'm going through with son and engine swap on a 88 4runner: computers won't match. There are however places online that can reprogram but the smog places are restricted to tail pipe emissions and seeing if the obd system reports READY/OK. serial number only makes the mechanic not have to find, copy and report the one on the dash.

All the computers I have come across prior to 2015 don't have embedded non changeable serial numbers, would fubar a non dealer repair shop doing a swap.

So I would go see if thats an actual requirement. I would also research spoofing various sensors: fuel pressure, O2 pre cat, TPS, rpm what have you

First question: 1988 4runner?? Did it even have a PCM??

I believe these 03 Can be programed with the VIN, but that cost$ and may also need to be reprogrammed to the Key as well. Vin I am told is required.

I am giving spoofing a serious look into...

As for your tag Line: "There are some "experts" out there that in reality don't have a clue as to what they are doing."

I break Experts as EX: past tense, and perts: a drip under pressure...

[Piotrsko]

No I made up the story we're looking for a pcm as a joke. The pcm in an 88 is vacuum inputs for controlling the electric FI which wont be there with the 98 engine we're installing. Problem is he has a manual trans which is super hard to get a computer for and in toyotas it matters to the system. If I had a couple to ruin, I have a universal programmer that will write to anything in binary with a 4pin memory access.

The post comment deals with the so called authorities prevelant on forums like these with incorrect inflexible concepts regarding how things actually work. Hit a nerve?

[Grant-53]

The vans and trucks are higher drag shapes than a sedan.

[racprops]

Here we go again:

* The first two vehicles you compare are a Grand Marques and a Crown Vic. Both ordinary, and similar, low height sedans whose MPG performance matches reasonably. The faster you went, your MPG went down marginally.


RAC Yes and both behaved normally, a little faster and a little less MPG.


* Then you posted numbers for a Ford Explorer. An SUV. (This is like comparing apples to oranges). Because the drag coefficient is so much higher (inversely, because it so much less aerodynamic), the fuel efficiency is going to diminish at an exponentially higher rate at higher speeds than a sedan.
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RAC And again that MAY be True, but HOW is possible to lose 10MPG speeding up from 50MPH to 60MPH and THEN ONLY lose 2MPG going from 60 to 70MPH, and again ONLY lose 2 more MPG going to 80MPH?? Do the Math, exponentially higher rate at higher speeds so going at 80MPH SHOULD CAUSE A EVEN GREATER lost of MPG RIGHT??

RAC Also I drafted a big rig in I10 Northbound and got within ½ a car length and NO CHANGE

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You have also completely disregarded weight. The heavier an object is, the more energy it takes to propel it at a given speed.

RAC Your forgetting Nurton’s Third Law, a object as restt needs a force to move, and an object in motion will require force to stop it….a moving car or SUV at speed cruising needs very little force to MAINTAIN the speed…

My 03 Ford Explorer:
Power / Horsepower 239 HP @ 4750 rpm
Torque 282 ft-lb @ 4000 rpm

Curb Weight 4,381 lbs
2003 Crown Vic 3,942 lbs.

SUV is 439 pounds heavier the 03 Crown Vic about two full grown men.

The 2003 Ford Explorer has a drag coefficient of .41 Cd.
The 2003 Ford Crown Vic has a drag coefficient of .37


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This is not a programmed decrease in relative performance by Ford. If so, there would have been hundreds of class action lawsuits and federal investigations by now.
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RAC NO ONE questions it…you are dead sure I am wrong, you did not even fully read my points…everyone is 100% sure it is true, Trucks, SUVs and Vans CANNOT get good MPG BECAUSE of air resistance.

Part of why older trucks got bad gas mileage was because they were built to do what a truck was excepted to do, haul heavy loads, SO they were geared and carbed FOR that job, it just was not possible to build them both ways. Many trucks have a highway setting and a towing setting…

RAC Now with computer controlled system it could be done…by no one but a few people like me want better gas mileage and the answer is always buy a tinny little car. And very few have ever LOOKED for this…

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Your economic assumptions for MPG improvement cost savings are baseless. When talking about things like running 16.4 AFRs, water mist blended in with fuel injection, and what not.
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RAC GM did that 16:1 Air Fuel ratio trick in the PCMs of the 1985 to 91 Camaro’s with 305 and 305s running the TPI system. It was not allowed or used here BUT in Australia and New Zealand, it was. And I testing my 2000 Mercury was able to control its fuel ratios and gained a 5MPG by running 16.4.

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If you really want to improve your MPG measurably and at NO cost, put more air in your tires, drive defensively, obey the speed limit, and change your engine oil and air filter frequently.
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Done and Done, and you cannot see, read, of get any real change in MPG.

So I will keep trying to find an low cost way to correct this trick in two SUVs, which by the way one is 02 4.0 V6 and the other a 03 4.6 V8 and get one MPG difference between them.