Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - Ultragauge and Lean Burn

darcane · 09-24-2012, 08:36 PM

OK, so I know the Ultragauge doesn't read Lean Burn properly, and bases mileage off air flow rather than fuel flow. So... is there a good rule of thumb to estimate it? I watch the O2 sensor to determine if it's in Lean Burn or not.

If my UG shows 40mpg and it's in Lean Burn mode, I assume that is figuring about 14.7 A/F ratio. If I assume a 19 A/F ratio, can I estimate my instant MPGs are 1.3x higher, so 52mpg?

Or is it not this straightforward?

09-24-2012, 08:36 PM	#1 (permalink)
darcane ......................... Join Date: Aug 2009 Location: Buckley, WA Posts: 1,597 Thanks: 391 Thanked 488 Times in 316 Posts	Ultragauge and Lean Burn - Estimate MPG? OK, so I know the Ultragauge doesn't read Lean Burn properly, and bases mileage off air flow rather than fuel flow. So... is there a good rule of thumb to estimate it? I watch the O2 sensor to determine if it's in Lean Burn or not. If my UG shows 40mpg and it's in Lean Burn mode, I assume that is figuring about 14.7 A/F ratio. If I assume a 19 A/F ratio, can I estimate my instant MPGs are 1.3x higher, so 52mpg? Or is it not this straightforward? __________________ Past Cars: 2001 Civic HX Mods CTS-V 2003 Silverado Mods