mpg
#11
Re: mpg
I had one tank off 2.5 mpg (indicated higher than acutal), but most tanks are about 1mpg off. Check my mileage - I usually post the indicated mpg in the notes for the tank. I always enter the manually calcuated mpg in the database.
#12
Re: mpg
Originally Posted by spiff72
I am thinking they might be discounting for a limited time - $1.99 seems too low - especially when they are pricing the midgrade $0.30 higher.
It is funny that I posted that and the next story on the news was about the dropping prices - with the average at $2.62 nationwide (according to ABC news).
It is funny that I posted that and the next story on the news was about the dropping prices - with the average at $2.62 nationwide (according to ABC news).
#13
Re: mpg
My last tank had an indicated of 41.8, actual was 41.9 mpg, so I was happy with that. However, it is usually indicating more than actual. I use the indicted mileage as a guide to how I am doing but I don't count on it. I am a 90 to 95% highway driver, and I drive about 2500 to 3000 miles a month. My new TCH has just over 3000 miles and I bought it on August 10.
In NC we are down to about $2.33 for regular at the cheapest stations. Summer driving season is over!
In NC we are down to about $2.33 for regular at the cheapest stations. Summer driving season is over!
Last edited by faldoc; 09-13-2006 at 08:54 PM. Reason: correct typo
#14
Re: mpg
I was working with my dealer's service folks on another issue (see my post in the nav thread coming shortly).
As they understand it, the 'real-time' mpg and computed MPG are calculated by a formula involving gas engine rpms and speed, based on average gasoline used during an engine cycle. This would probably explain the majority of discrepancies as I doubt the exact same amount of gas pumps into the chamber each stroke.
This also strikes me as probably the best way to do it from a technical standpoint, I doubted they would have put a few flow monitor of that exactitude in the car.
As they understand it, the 'real-time' mpg and computed MPG are calculated by a formula involving gas engine rpms and speed, based on average gasoline used during an engine cycle. This would probably explain the majority of discrepancies as I doubt the exact same amount of gas pumps into the chamber each stroke.
This also strikes me as probably the best way to do it from a technical standpoint, I doubted they would have put a few flow monitor of that exactitude in the car.
#15
Re: mpg
I'm not sure about that - I think that they CAN measure fuel flow pretty accurately. Fuel injectors are VERY precise devices, so i think that they could use the number and duration of the pulses of the injectors to determine the amount of fuel used.
#16
Re: mpg
Oh I am certain they could, the question is the economics of putting one in. Assuming the injectors are calibrated properly, you could base your numbers on the calibrated amount and be pretty close, based on what we've seen.
Also, we could not find anything that looked like a fuel meter on the parts list.
Also, we could not find anything that looked like a fuel meter on the parts list.
#17
Re: mpg
Originally Posted by Loonbeam
Also, we could not find anything that looked like a fuel meter on the parts list.
The fuel usage was measured by the fuel injector's pulse width.
Ken@Japan
#18
Re: mpg
Denver is about $2.69 for regular grade - but our regular grade is = to everyone elses poor or economy grade... Some gas stations in the midwest/east have an economy grade which is our regular grade - only 85 octane. So I always have to put in midgrade (87 Octane) in Denver....but yet they still price it like the rest of the nation - so we are getting nailed twice - cheaper gas for the same price as the rest of the nation... So 87 octane gas here is still running about $2.79 - 2.99....