Quote:
Originally Posted by Mohammad Abdullah
I did NICEoff for only a few minutes each time but twice on a hill, I must have reached 75 mph and 4 miles  all other times were about 35mph for a flat mile. Now I'm aware, the miniscule mpg benefit of NICEoff probably isn't worth the potential $100s repair.
For NICE on, is the mpg savings actually significant? I believe idle rpm is like 1 US gallon per hour + don't have to hit the gas at the bottom of the hill VS engine braking using zero gas + accelerator at bottom of the hill. Are there any conclusive results? Thanks everybody |
My 2.4 accord used something like 0.21 gallons per hour, the V6 accord does around 0.34. Yes, the savings can be significant, especially if you live in a hilly area.
I did set up a test of fuel cut vs idling in neutral, but my scenario didn't really allow for much speed difference. So I went 40 mph in 5th gear and let off the gas, then tried again coasting in neutral. I didn't have much of a run up area, so it could have been enriching fuel. My car also has rev hang, so it didn't drop to idle right away when coasting in neutral. Both tests I let the car go from 40-22 mph, which is where 5th gear will return fuel. I tried to arrive at the same spot as well by maintaining speed for a little bit before fuel cutting.
Coasting in neutral was around 60 MPG, in gear was around 70 MPG. The test was flawed as I really needed a larger run up area, among other things. Ideally I would also downshift and continue fuel cutting in lower gears until a minimum speed, but the scangauge doesn't necessarily catch quick transitions in fuel consumption. Instead i'll see if I can redo the test on a higher speed road, doing a 50-30 mph test in 6th gear vs neutral. Maybe 5th gear as well.