I read this online today and wanted to know if this was really true? And if so, does it apply to the 08 E350?

Most fuel-injected engines today use computer-controlled Deceleration Fuel Cut Off: When you lift your foot from the gas while leaving the car in gear, injectors shut off automatically, and the car's rotating tires—which are connected to the engine via the transmission—keep the engine turning and the accessories running. So, the engine consumes no fuel at all while the vehicle is coasting downhill.

 

Yes, have heard the same thing...Belive it is true

 

So at what point to the fuel injectors kick in again? You certainly cant be stopped at a red light with your engine running and not using fuel. Do the injectors kick back in at 10mph, 5mph, 1mph, or when the car comes to a complete stop? Just curious.

 

Maybe this is why when my Volvo S80 coasts downhill, it reads an instantaneous gas mileage of 99 MPG! Too bad the W211 does not have a way to view the instantaneous MPG...

 

it's been touted as an advantage of injection even back 60+ years ago.

In the early days of smog controls, some of the manufacturers tried to incorporate an idle circuit cut-off into carbeurators, too, but they were troublesome.

 

Been an installed feature since the 1980s

VERY dangerous on snow/ice with manual transmission