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Old 02-02-2010, 05:25 AM   #7 (permalink)
aero guerrilla
Piwoslaw's Avatar
Join Date: Oct 2008
Location: Warsaw, Poland
Posts: 3,614

Svietlana II - '13 Peugeot 308SW e-HDI 6sp
90 day: 58.1 mpg (US)
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Originally Posted by Arragonis View Post
Piwoslaw - how did you determine the scale of the error on your built in meter ?
The factory instrumentation has two resetable modes (which I reset after each trip and each fill up, resp.) and an instant consumption mode. Each trip and each fill up is noted (distance, l/100km, avg km/h, where I went, weather and/or traffic conditions if out of normal). After each fill up I do the math and compare the fuel/distance with the l/100km for that tank. Since in both cases I use the car's odometer I don't have to factor in the 5% difference between odo and GPS (that comes later). I've also noticed by doing even more math that the individual trips don't add up to the tank, but that may be b/c of the computer rounding up or down after each trip reset.

At the Peugeot forum I found out that pretty much everyone's onboard fuel computer is off by 0.5-2l/100km, some are too high, others too low. The funny thing is that the differences between the car's comp and actual fc varies with each tank. The difference may depend on the number and length of trips in each tank, but my investigations haven't gone that far.

I understand that a ScanGauge can be calibrated, so after a few tanks it should be right on? I guess that when my consumption gets even lower I'll need the SGII to refine readings, since the comp seems to be off by more when my fc is lower. And USD/EUR is still fluctuating in the wrong direction
e·co·mod·ding: the art of turning vehicles into what they should be

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[Old] Piwoslaw's Peugeot 307sw modding thread
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