Dean_W
Member
Registered: 13th Dec 05
Location: Downham Market, Norfolk
User status: Offline
|
How do they work?
Are they really accurate?
|
Tiesto
Member
Registered: 6th Jun 02
Location: Hinckley, Leicestershire
User status: Offline
|
Aint a clue how the work, but mine is not accurate, it works out i get 3mpg less than what it actually says.
|
nova_gteuk
Member
Registered: 15th May 02
Location: South Wales Drives: The Bandwagon
User status: Offline
|
The ECU knows your speed in miles per hour,and it knows the fuel flow in gallons per hr,there is a flowmeter in there somewhere-or an indirect flowmeter based on the pressure and number of squirts, duration of squirts of the Fuel injectors(or fuel pump).
|
Dean_W
Member
Registered: 13th Dec 05
Location: Downham Market, Norfolk
User status: Offline
|
Rite..........
|
deano87
Member
Registered: 21st Oct 06
Location: Bedfordshire Drives: Ford Fiesta
User status: Offline
|
But if you want to work out as true MPG as you can.
Fill up to the brim, reset odometer thing.
Wait until you next fill up. Make a note of the miles from odometer. Fill up again to the brim. Get a receipt detailing litres purchases.
Litres x 0.22 = gallons.
Mileage / gallons = MPG
|
GT190
Member
Registered: 6th Dec 07
Location: Greater London
User status: Offline
|
or http://www.torquecars.com/tools/uk-mpg-calculator.php
|
Dean_W
Member
Registered: 13th Dec 05
Location: Downham Market, Norfolk
User status: Offline
|
quote: Originally posted by GT190
or http://www.torquecars.com/tools/uk-mpg-calculator.php
39MPG......
|
Dave A
USER UNDER INVESTIGATION - DO NOT TRADE
Registered: 10th Dec 03
Location: County Durham
User status: Offline
|
most OE systems work on a calculation of engine load i.e throttle pedal position, engine speed and an RPM reading.
|
myke
Member
Registered: 7th Feb 01
Location: High Wycombe, Buckinghamshire
User status: Offline
|
digital mpg gauges are as said.
economy meter gauges like on mercs and beemers are just vacuum from inlet as far as i'm aware, and they calibrate the backing to be close to accurate. the scales usually aren't constant though, so they're not that great.
|