Does your MPg readout agree with gas station calc?

My Toyota has an average miles per gallon reading which is consistently about a mile a gallon higher than the gas pump/hand calculator method says I get on a fillup.

My '94 BMW gives the mileage since the last reset, and I can reset on fill ups. I actually have two averages, CONSUM1 AND CONSUM2. I can reset them independently of one another, so I can have the average since the last fill up, and the average for the entire trip -- or any time period that I want.

It is accurate within a few hundredths of a mile per gallon.

Tire wear shouldn't have an effect that you would notice. If you wanted to carry out the calculation to four or five decimal places, you might be able to see tire wear, but to do this you would have to isolate weather conditions, your excessive mashing of the throttle, and other things that have more effect on mileage than tire wear will have.

Smart people don't need the car to calculate the mileage. We know how to divide the distance travelled by the fuel purchased to arrive at how many miles per gallon we get.

Speaking of this, do the modern Corollas have MPG readouts?

That would be a handy gauge if they could do it. It would help us drive for the max MPG when possible.

Any Dodge (Chrysler / Jeep) with a mini-trip computer has it. My '95 Grand Caravan SE does (20.9), a Ram 2500 5.9 Cummins 24V had it (11.6 pulling a

Our '93 Lincoln Continental had it, as did other early '90s Fords with the digital cluster.

Agreed that it should be a standard feature on all cars, they all know fuel amount injected and distance traveled.

Not my 05.. The 02 Impala we had had one. But I don't think they are super accurate, and really only an appx guess. Kinda like a glorified vacuum economy gauge on steroids. Nothing will trump measuring the fuel added, measuring the miles driven, and using plain old math to see the result. I do have a GPS in the car, so I know exactly how many miles I drive for any given trip. And with the odometers, even that is truly not needed to get an accurate number. The GPS just verifies what the odometer says. Needless to say, I know exactly the mpg my car gets at the various speeds I drive. Getting the max mpg is easy. Keep the weight in the car down to the lowest possible, and keep the right foot pressing the gas pedal at the least pressure required to attain and maintain the desired speed. Keeping the tire pressures up will make a large difference too. IE: 32 psi will do quite a bit better than 26 psi, but with a slightly rougher ride. I prefer max economy vs boat like ride.. :/ So I run at least 32 psi at all times. And even with 32 psi, the ride is not bad. If I'm carrying a lot of weight, I might even bump to 34 psi at times.

If you need a guage to tell you that you are not getting the max mpg possible, then you will never get the max mpg possible. If you were getting the max mpg possible, you wouldn't need a guage to tell you.

In message , Chuck Olson writes

My Auris has both instant and average readings and I find that if anything the average reading is normally a little pessimistic on runs about town and can be 10% low on long (300mile) journeys where 55 to 60 mpg is the norm. (Constant 70mph motorway.)

So why not just reset your mpg when you fill your tank? Then the next time, you'll have a closer, albiet off, reading.

Speak for yourself. Not all of "us" are.

Why not, instead, campaign for gas prices to be back where they should be instead of filthy-high to line the pockets of BP, Exxon etc?

Lets not. You can buy one and add it if the car you want doesn't have one. No reason to legislate to force those who don't care to pay for something because you do.

But if they were done electronically, they could monitor several factors. Vacuum, fuel flow, speed, for example.

Not instant feedback though.