the never empty gas tank

[1fastpizzaboy]

I have read everything I could find and have checked the computer using the diag mode. my fuel guage works fine. eveything works with one annoying exception, the dte won't read below 250mi.. when I fill the tank, dte goes to 500 mi.. now I don't know about you guys, but there's no way in hell a mark EVER got 500mi out of a tank of gas!:confused: anybody got a fix for this?

[lsc7]

IF mine did that, i wouldnt complain... Im tired of always hearing that beeping.

now i understand that filling the tank stops the beeping, but i was in college and couldnt afford a full tank... haha hope that changes now.

[ekooke]

I have read everything I could find and have checked the computer using the diag mode. my fuel guage works fine. eveything works with one annoying exception, the dte won't read below 250mi.. when I fill the tank, dte goes to 500 mi.. now I don't know about you guys, but there's no way in hell a mark EVER got 500mi out of a tank of gas!:confused: anybody got a fix for this?

Actually, a properly maintained Mark VII with a ±22 gallon fuel tank and a 25+ mpg rating has at least a 550-mile highway range. Yours does sound as if there's an accuracy problem, either at the TM, wiring (ground), or the fuel gauge/TM internal interface on the digital model, or the 4-post interface module or 3rd sender wire being lightly grounded on the analog gauge model. Try the TM tune-up at: http://www.lincolnsonline.com/tech/00022.html
Check out the TM functions at: http://www.lincolnsonline.com/tech/00004.html
Do the Ground Fix at: http://www.lincolnsonline.com/tech/00109.html

[skymasteres]

I got around 520-540 miles out a few tanks on a road trip from New Jersey to Indiana.

[1fastpizzaboy]

everything works so no tuneup needed! all of my analog guages are accurate and my tm is accurate. The dte even works. the problem is it's viewing empty as 250mi! any way to reset the system? what number is the tm fuse?

[ekooke]

everything works so no tuneup needed! all of my analog guages are accurate and my tm is accurate. The dte even works. the problem is it's viewing empty as 250mi! any way to reset the system? what number is the tm fuse?

What makes you think, "fuse"? It's working, isn't it? Anyway, now that it's been established that the car has analog gauges, it's most likely the 4-post interface module on the back of the instrument cluster or the 3rd sender wire being lightly (frame) grounded going to the interface module.

[Tony T]

everything works so no tuneup needed! all of my analog guages are accurate and my tm is accurate. The dte even works. the problem is it's viewing empty as 250mi! any way to reset the system? what number is the tm fuse?
Try disconnecting the battery for a minute,this will reinitialize the MC. If this don,t work,there are a couple of things that determine the DTE, fuel left in the tank and the average mpg your getting. Does your mpg seem unreasonably high? Do the self test by pressing clock and miles buttons at the same time. Now press the 3 button, this will show fuel in the tank, compare it with gauge, full tank=19 to24.5, empty= 0 to 3. press the 2 button, fuel flow (which determines mpg) the number shown will steadily increase with engine running and fuel is consumed. The fuel level comes from the sender in the tank via the interface module and the fuel flow comes from the EEC. Start with this, more to come if needed.

[Bluegrass]

Fuse 16 a pink, should reset the Trip Minder if removed a few seconds.
I would not remove power from the whole car as this reboots the engine computer that has to learn your driving all over again, unless you don't care.

[88-lincoln]

NOTE: Do Not proceed with following information.

I got so sick of my nonfunctional Tripminder that I just ripped it out. Saved it, of course.

[1fastpizzaboy]

I set the test mode and took the mark fOR A LONG drive and I found out the fuel button stayed at 25.5, for 160mi.! so a bad fuel sender it is i guess.:(

[ekooke]

I set the test mode and took the mark fOR A LONG drive and I found out the fuel button stayed at 25.5, for 160mi.! so a bad fuel sender it is i guess.:(

Does the gas gauge seem to work correctly? If yes, the fuel sender itself is OK.

[Tony T]

As ekooke says don,t count the sender out yet if gauge seems right. Could be the interface modual is not seated properly on the back of the cluster. The fuel level signal travels from the cluster via pin 9 and goes to pin 8 of the MC crt.205 db/lg.

[Tony T]

Oh yeah also check cluster pin 10 (fuel sender to interface modual) crt. 204 o/Lb.

[OneWayStreet]

Actually, a properly maintained Mark VII with a ±22 gallon fuel tank and a 25+ mpg rating has at least a 550-mile highway range.

On a side note, I was pleasantly surprised to discover this driving the Power Tour. :) Best mileage was 26.8 MPG.

Driving my other vehicles, I'm used to needing gas around 300-350 miles.

End of hijack. :cool:

[1fastpizzaboy]

well guys.
I think i have a ground problem.
my guage was right at the red mark when i noticed something, in the test function flow was reading about 3.5. i was listening to the radio and the lights and motor were off. when i turned the motor on, the reading jumped up to 15.5! i turned the motor off and the reading went back to 3.5. i turned the lights on and the same thing happened. now the fuel sender was suspect until i went to the gas station and started to fill up. the reading was accurate to the gallon. so looks like i'll be grounding this thing down. does anyone make a complete 5.0 engine ground kit?(might as well kill all groung gremlins at once.)