Recalibrating Fuel Computer MPG

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Does anyone have info on setting the overhead computer so it reads correctly ???

First one with the right answer gets a free Cummins Screen Saver #ad


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"Have you driven OVER a phord lately"
2001 2500 BRT WHT SPORT QUADCAB 4X4 ETH 3. 54LSD TRLR CMPR PKG ALL OPT XCPT LTHR

 

[Archive]

My guess would be to ask the dealer.
Big A

 

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I remeber a post about that a while back. Something about holding down both buttons for 15 seconds or longer until the readout flashed then a 0 comes up and can be adjusted +or- a couple numbers.

This could also enable the selfdestruct timer so be carefull #ad
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It's too cold out right now to go to my truck and check, but isn't this covered in the manual? I know I just recalibrated the compass last week, and you zero out the current numbers by pressing both buttons... .

Check your manual for specific instructions for each function. It's fun! #ad


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2001. 5 2500 SLT+, QC/LB 4x4, ETH, 6spd, 3:54 LSD, camper/tow equip. , NV241HD, Bright Silver, Snug Top, Ispro w/3 pod pillar w/tweeter, Pyro, Boost & Mag Hytec cover w/temp guage, no decals and no emblems.

 

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The computer calculates fuel mileage by using inputs from miles traveled and the throttle position sensor. Since the TPS will vary depending on engine load and driving/driver conditions I don't see how it could ever be "accurate". Just my observation. bg

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White 99 3500, QC, 3:55, auto. most options except leather, Line-X bed liner, fiberglass running boards Rancho 9000s, bug shield and window vents, black vented 5th wheel tailgate, 100 gal. aux. fuel tank.

 

[Archive]

Just sat here and went thru my owners manual... a 1999.
Nothing in there about recalibrating the fuel computer. Only resetting it to zero when ya fill up.

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Rob Hanson
1999 "Big Red", 3500 SLT QC 4X4 6 spd, 4. 10 LSD, Braided SS fuel lines, Mag-Hytec Rear Cover, Cummins E-Brake, Blue Box, DD3 Injectors, Banks High Ram and 14cm Wastegated Turbo, All-steel Cowl Induction Hood, Cummins RED Valve Cover, Rhino, Rosewood Kit, Scotty System, SportComp Gauges, TorkLift SuperHitch, Tekonsha Brake Controller, Rear Flood lights, Cobra CB, DeeZee Running Boards, BD 2WD Low kit, Air Lift bags and a Geno's "I tromped a Ford" decal. Member of BOMB! (WW NW Chapter)

MyPics.com (pics updated 10/14/00)

I'd rather be... .
Cummin than Strokin.

 

[Archive]

Originally posted by KWIKKURT:
Does anyone have info on setting the overhead computer so it reads correctly ???

First one with the right answer gets a free Cummins Screen Saver #ad

Do you mean "accurately" rather than "correctly"? The MPG readout is a mathematical answer to miles driven divided by gallons used. It actually resets itself every few seconds depending on how hard you are accelerating etc. and gives an estimated MPG based on those inputs. It gives the MPG figures based on how you are driving "right now". DC informed me to use it as an estimate while driving but to calculate accurate MPG upon filling up.

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Mark Schlueter
New Dodge and diesel owner. 2001, QC, 4x4, ETC, K&N, White sport package. Just installed Kodiak Sidewinder Steps. Good product, easy install.

 

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I assume that you want to know because you have either a fueling box or non-stock injectors... .

I haven't found a way yet. I wish I was getting the mpg's that the computer says that I am #ad


If you find out please let us know.

Berserker

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99 2500 QC LB 4x4 Auto, Laramie SLT, driftwood. Cummins 24v w/ 275 HP injectors, Edge Products EZ & Banks Stinger Plus kit minus Ottomind, TST 10 level PM3, Stainless Steel fuel lines, EGT and Boost gauges on A-Pillar mount, Prime-Location fuel filter kit (removed pending outcome of testing), MagHytec Diff and Trans covers, ConFerr front heavy duty axle truss w/skid plate, EZ Change oil drain plug, BFG 35x12. 50x16. 50 MT's, Tuff Country 5” stage II lift-kit, Rhino liner, Smittybilt nerf bars, Warn chrome Transformer brush guard w/Warn12000 winch, Tow Hooks, Xenon fender flares & Abbott Electronic Ratio Adapter. DTT's Valve Body & Torque Converter.

MyTruck

 

[Archive]

My MPG is always . 5 to . 7 MPG better than computer says

 

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Chris,

It's better than the 6 MPG difference that my computer shows #ad


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99 2500 QC LB 4x4 Auto, Laramie SLT, driftwood. Cummins 24v w/ 275 HP injectors, Edge Products EZ & Banks Stinger Plus kit minus Ottomind, TST 10 level PM3, Stainless Steel fuel lines, EGT and Boost gauges on A-Pillar mount, Prime-Location fuel filter kit (removed pending outcome of testing), MagHytec Diff and Trans covers, ConFerr front heavy duty axle truss w/skid plate, EZ Change oil drain plug, BFG 35x12. 50x16. 50 MT's, Tuff Country 5” stage II lift-kit, Rhino liner, Smittybilt nerf bars, Warn chrome Transformer brush guard w/Warn12000 winch, Tow Hooks, Xenon fender flares & Abbott Electronic Ratio Adapter. DTT's Valve Body & Torque Converter.

MyTruck

 

[Archive]

My computer is the same as Chris as mine tends to read anywere from . 5 to 1 MPG lower than actual mileage, but when I use the PE is reads consitantly 1 MPH too high, ohwell.

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2001 2500HD Quad Cab SLT SB 4x4, HO Cummins, 6-speed, 3. 55 gears, LSD, brightwhite/driftwood, 4w ABS, camper and trailer tow packages, HD transfer case, snow plow prep, group, cab lights, Isspro Boost and Pyrometer gauges mounted on A-pillar, 4" JRE exhaust, BD exhaust brake. 22500 miles as of 11/11/00.

1980 CJ-5, Modified for off-road use, bobbed fenders, 350 TBI, NP435 trans, 4. 56 gears, Dana 300, Dana 44 front, Dana 60 reverse-cut rear axle, ARB air lockers front and rear, 15/35/15 Super Swamper TSL on 10X15 steel rims, Cobra CB, Warn 9000I winch, nerf bars, 1/4" steel rock crawler bumper front and rear, jerri can/spare tire rack, custom roll cage.

 

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I stopped paying any attention to my trip computer because it's so far off. Mine regularly shows me getting 15. x mpg, but when I fill up and calculate it myself, I'm actually getting 13. x mpg.

Hmph.

Rob

 

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Mine was 1 mpg off till I put in injectors. Now it's 4 mpg off. I too wish I was getting what it shows.

Steve

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Y2K 3500 SLT+ 4X2,auto,3. 55,VA,275s,PS mod/elb,K&N,DTT TC&VB,SPA Boost/ETG&Tran Temp/Pres,JRE 4" exhaust,Roadmaster Susp,Rhino-liner,Eagle Series 58 Wheels

 

[Archive]

Like others, I think it would be great if the trip computer was based on miles driven/fuel used and thus could be accurate. However, I must add that I love this gadget anyway - mine is off, but fairly consistently off. So it still gives me a good relative idea of how I am doing without having to wait until I run a full tank through. I can pick a speed, then immediately see which gear is giving me best mpg at that speed, and I can see the effect of speed changes and headwinds. "Accurate?" - maybe not. "Option worth having? - Definately!

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2001 ETH, QC, LWB, 4WD, 3. 54, SPA Pyro & Boost, K&N RE-880 w/foam pre-cleaner, ARE Z-series Cab-high shell, Rear ARB locker, and all kinds of synthetic fluids...

 

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Thanks for the Replys to my Question. .

HC... I agree with you. Even though mine is almost 3. 5 mpg off since installation of Inj's and EZ it is still useable information for helping read current and Avg if not accurate mileage performace. .

I am sure the Fix or Adjustment is in the interface between BCM (Body Control Module) and the ECM. IMHO The display is only that; a display that just displays information. . The computations are most likely done in the BCM with information from the TPS (throttle position sensor), Rpm and the BCM VSS(Vehicle Speed Sensor).

A friend at D/C is checking to see if they can Bomb (I mean adjust the mileage computer reading)... Of course we might run into a warranty issue #ad
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Just kidding!!!

<fontcolor=blue>"I am my own Warranty, Research, Developement and TEST Station"

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"Have you driven OVER a phord lately"
2001 2500 BRT WHT SPORT QUADCAB 4X4 ETH 3. 54 6 Spd LSD TRLR CMPR PKG ALL OPT XCPT LTHR. . 32,500 miles #ad


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[This message has been edited by KWIKKURT (edited 12-17-2000). ]

 

[Archive]

Originally posted by Big A:
My guess would be to ask the dealer.
Big A

Mine was off 2 to 3 mpg high. I asked the 5***** and they said boy thats real close,but they would call DC and fine out. Reply was [ about normel ] and I wonder for a Dodge or for trucks?

 

[Archive]

There goes my theory #ad

Big A