View Single Post
Old 04-30-2013, 04:09 AM   #18 (permalink)
AndrzejM
Master EcoModder
 
AndrzejM's Avatar
 
Join Date: Oct 2011
Location: Poland
Posts: 840

Berta - '97 BMW 318 tds Compact
90 day: 62.03 mpg (US)

Charlie - '07 Citroen C4 Grand Picasso Exclusive
90 day: 37.58 mpg (US)

Corsa - '05 Opel Corsa C
90 day: 53.22 mpg (US)

Mruczek - '03 Audi A2
90 day: 60.61 mpg (US)
Thanks: 185
Thanked 167 Times in 117 Posts
Quote:
Originally Posted by stewie View Post
That's great explanation. Thank you. Sorry for so many questions but i'm trying to understand this device better and without set values i just don't know. My tank is just running out now, another day or two so i would like to get settings correct so i can test with full tank. It takes 2 weeks to empty my tank so if i won't get it right it will probably take few tires so few months.

I did GPS speed test today and MPGuino showed slightly slower speed then GPS app on my phone. I believe GPS on my phone showed same speed as speedometer in car HOWEVER my speedometer in car is incorrectly slightly as my tires are one size bigger 175 instead of 165 as you that's how i bought the car. So if i understand you correctly my vss/m and MicroSec/Gallon will be different then default of (vss/m = 8208 MicroSec/Gallon = 0279235000) due to slightly bigger tire size?

Should i adjust VSS delay to get speed right or VSS value? Also mpguino does not have rpm guage. I do notice instant mpg changes as soon as i change any values including REVS and Delays.
Pity v0.86 doesn't have rpm gauge. My "canadian" metric version has it and it's great for diagnostics. But if you mounted MPGuino on your own you can change the code and set up rpm gauge. I can look into the code and provide you all the changes that you need to do that.

Anyway - you've mentioned that your speedometer can be off due to different than oem tire size. Speedos are off very often by 5 to 10% so don't worry about that. You may calibrate it (mentally) with GPS and that will give you how big is the difference.
But if speedo is off then probably your odo is off too. You should check the difference with GPS or mile markers (10 miles or more), to be sure what exact distance you're doing on the tank. Then you can calibrate MPGuino for the exact value and relay on that to get your FE numbers.
__________________


Quote:
Gerhard Plattner: "The best attitude is to consider fuel saving a kind of sport. Everybody who has enough money for a strong car, can drive fast and hit the pedal. But saving fuel requires concentration, self-control and cleverness. It's a challenge with the nice effect of saving you money that you can use for other more important things."
  Reply With Quote