Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - Civic EPES: Alternator Delete Project (with additional lithium battery...)

brucepick · 04-12-2012, 10:04 PM

After driving several tanks with the EPES which runs mostly around 12.5V instead of the alternator's approx 14V, I found my MPGuino consistently reporting somewhat more fuel usage than the car actually consumed.

I expect that the fuel pump is running at somewhat reduced pressure at the lower voltage. So for any given injector pulse length, less fuel is being injected. The MPGuino reads pulse length, so needed an adjustment for use with the EPES.

Anyway, the correction I needed was right around 3%.
FYI. YMMV.

04-12-2012, 10:04 PM	#124 (permalink)
brucepick OCD Master EcoModder Join Date: Dec 2007 Location: Eastern CT, USA Posts: 1,936 Outasight - '00 Honda Insight Team Honda Gen-1 Insights 90 day: 54.18 mpg (US) Thanks: 431 Thanked 396 Times in 264 Posts	EPES required MPGuino recalibration After driving several tanks with the EPES which runs mostly around 12.5V instead of the alternator's approx 14V, I found my MPGuino consistently reporting somewhat more fuel usage than the car actually consumed. I expect that the fuel pump is running at somewhat reduced pressure at the lower voltage. So for any given injector pulse length, less fuel is being injected. The MPGuino reads pulse length, so needed an adjustment for use with the EPES. Anyway, the correction I needed was right around 3%. FYI. YMMV. __________________ Coast long and prosper. Driving '00 Honda Insight, acquired Feb 2016.