This actually supports what I said. The reason the RPM goes up is there's no more resistance. It's like if you open a door when someone on the other side is opening it already.

That's why even if you don't press the gas (or brakes) while in D, the car already goes forward. But if you're in N, it'll only move if gravity pulls it.

I think you misread. I didn't imply the engine keeps the car still. A stopped car's RPM cannot be linked to its wheels or else it'll stall.

 

I don't know if this answers anything but. My scan gauge tells me that I burn .20-.22 GPH in neutral, and .27-.28 GPH in gear with the auto. Lights add about .02-03gph.

9840 miles with 245 gallons since new. 40.1 MPG

Stock FIT Sport with auto. Scan Gauge, and 46 psi in the tires. Mobil 1.

Love you enemies,
But don't buy their oil!

 

If you drive a MT, you should be in neutral at stop lights, the only difference is in neutral with the clutch out you are spinning the input shaft, but that is insignificant drag compared to holding the clutch in...

but more importantly, if you hold the clutch in at all your lights, you are going to quickly wear out your throw out bearing,
your goal with a MT is to keep the clutch out, as much as possible


as for AT, technically there is less drag when in neutral, but i doubt you would see anything from it, and all that shifting in the tranny from d to n each time, is not worth it

 

46psi, is way too high, the max for most tires is 40
your running the risk of a blowout, and bad tire wear

but 40 mpg....nice