Join Date: Apr 2009
Location: Simi Valley, Southern California
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Intelligent Deceleration Fuel Shut-Off (iDFSO)
I was searching around today trying to find more information on the fuel shutoff feature. It is included in both the auto and the manual transmission and that when you take your foot off the gas it shuts off fuel and uses momentum to keep everything moving. For the automatic this is a pretty obvious time, however with the manual I was assuming it doesn't work if you neutral your car down a hill. If it did this while neutral there would be no momentum since it isnt being transfed from wheels to engine and the car would stall out.
What this leads me to wonder is which would be more economical in a manual, coasting in gear which is going slow you down faster due to engine breaking but which will cut fuel and use momentum to keep the engine running or neutral the car and coast for longer without having to give the car gas, but never getting the fuel cut off because in idle it needs to keep the engine running. Or am I missing something that does allow the car coasting in neutral to cut fuel.
And to clarify, this system exists seperate from MDS and is in both manual and automatic cars.
Jazz Blue Challenger R/T Scat Pack 6M