A question for scangauge users....
 

How closely is the scangauge MPG reading correlated to a combination of throttle position and closed loop operation?

In other words...when you have closed loop operation AND minimal throttle position...do you have maximum MPG?

What other factors are involved? RPM range?

So possibly...RPM from say 1500 to 2500....closed loop...minimal TP needed to maintain needed speed = MAX MPG?

Different vehicles might need slightly different input variables to reach MAX MPG...but I'm looking for general relationships here.

My VW Cabrio (A/T) gets its highest continuous MPG from the lowest RPM I can maintain in its top gear. That's somewhere around TPS 7 to 10 and 1600RPM on the flats, which puts me in the high 30s/low 40s for speed.

You didn't ask about "practical." ;)

I understand that other vehicle/engine/transmission combos have different profiles and it can be possible to rev too slowly and hurt FE. If you're trying to work out what's best for your vehicle and you can't test it directly, try to get input from someone else driving the same model, or as close as possible.

Hope that helps,
Rick

That's where I am ('98 Integra A/T)-- if the RPMs are too low then -> +TPS -> (-)Timing Adjustments -> More Fuel, etc...

I get the most (when the engine is off :D )...
actually at 50 mph between 13-17 TPS = about 45 mpg. This is around 2000 RPM which is enough for TC lockup and momentum: otherwise, it starts to slow considerably and downshifts.

RH77