re: trip computers (a thread from last week)

["David J. Shield" <dshield@ns.net>]

John,

I checked my trip computer accuracy this week.  A combination of highway 
driving and city driving produced a trip computer reading of 14.1 gallons 
consumed, but the tanks took 15.4 gallons to fill.  14.1:15.4.  Far worse 
than I'd guessed.

Assuming the trip computer just counts injection pulses from the ECU, 
you'll need to count incoming pulses and deliver (to the trip computer) 
a corrected pulse count.  If the trip computer also factors in the pulse 
width of the pulses, you'll just have to play with the pulse width to 
perform the correction.  But I'm pretty sure the trip computer just 
counts the pulses.

Best,

David
'84 XJ6 VDP
'70 2+2 Etype

>If there is enough interest, I'll design a circuit to allow user 
>calibration of this.  Interested people, please e-mail me directly with 
>your current "percent of inaccuracy" on your fuel consumption reading.
>Please use the format X:Y, where X represents what your trip computer
reports, 
>and Y represents what the gas-pump typically shows.  For example, if your
trip 
>computer reports 20gallons, and the gas-pump shows 22 gallons, you would
report this as 
>20:22.  I need the info to get an idea of the range of inaccuracy people are 
>seeing.
     
>Thanks,
>John A.
>84 XJ6

---

• Prev by Date: Re: E-type digest
• Next by Date: D-Type wheels
• Prev by thread: re: trip computers (a thread from last week)
• Next by thread: XJ6 Series 1 Wheels
• Index(es):
  • Main
  • Thread