How To Increase Your Gas Mileage

Originally Posted by wstar

Well, if he's right about the fuel getting cut during engine braking, then yes engine braking would save more gas than coasting. However, I find this hard to believe. Cut fuel = no more combustion. The drivetrain would simply be spinning the engine and sucking air through the pistons for compression braking, but without any ignitions happening (which means really they could cut the spark plug current off too). I suppose in theory this sounds possible, but I would think I would hear the difference between an engine that's undergoing combustion and one that isn't, and I would think the transition between the two states would be rather abrupt and noticeable. Sure seems pretty smooth to me.

I'm not saying it isn't true, I'm just saying I find it hard to believe

Originally Posted by dad

There is a distinct change in pitch between accelerating and coasting.

Originally Posted by wstar

Agreed. I just find it hard to believe that what my ears are hearing during engine braking is just restricted airflow pumping through the cylinders with no combustion.

Originally Posted by wstar

Agreed. I just find it hard to believe that what my ears are hearing during engine braking is just restricted airflow pumping through the cylinders with no combustion.