Using data from the U.S. DOT, U.S. Census Bureau, and other sources, FinanceBuzz reveals how much of the average driver's monthly income goes toward gas costs.
The term “engine braking” refers to the braking effect that occurs in gasoline engines when the accelerator pedal is released. This causes fuel injection to cease and the throttle valve to close almost completely, greatly restricting forced airflow from, for example, a turbocharger. The restriction causes a strong manifold vacuum which the cylinders have to work against, sapping much of the potential energy out of the system over time and producing the majority of the engine-braking effect.[1] This vacuum manifold effect can often be amplified by a down-shift, which induces a faster spinning drivetrain to engage with the engine.
Engine braking is a viable method of controlling the speed at which a vehicle travels downhill. By shifting to a lower gear in a manual transmission, or applying “low” mode on an automatic transmission, engine braking reduces the need to repeatedly apply the foot brake, lowering the risk of the brakes overheating.[2]
Can use engine braking.
https://en.wikipedia.org/wiki/Engine_braking
Modern cars don’t seem to provide much braking from the engine, in my experience. Still some, though.