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My dad and I were talking about this the other day. I have a standard M5OD in my truck. If I am at, say 3,000rpm in any gear(i dont know if it matters which gear) with my foot off the gas, using the engine to slow me down, am I using more fuel vs at idle? Is the truck basically pushing the engine so it will spin on the idle amount of fuel? Or does the computer automatically put enough fuel in there since I don't have my foot on the gas?
Primary rig is Green Thunder:
95' F-150 XLT 4x4, 302, 5 spd, MSD 6A, Sunroof, CD player with 2 10" subs and some 32" BFG Muds .
Check out my Gallery for a look-see.
Then theres:
99' Mustang GT 4.6L
88' F-250 Superduty 4x4 351/c6
95' Mercury Cougar 4.6L V-8
80' E-350 300/6 with a
3 spd column shifter. Top speed is 65mph, Go Baby Go!
If it is fuel injected, the computer should turn the injectors off in that type of situation. So, technically, you should be using no fuel when engine braking.
Yes it is an EFI motor, the 95 below. My understanding is that it must use some fuel because you can hear it in the exhaust. I'm just curious if it uses more than what is at idle i would say is my question.
Primary rig is Green Thunder:
95' F-150 XLT 4x4, 302, 5 spd, MSD 6A, Sunroof, CD player with 2 10" subs and some 32" BFG Muds .
Check out my Gallery for a look-see.
Then theres:
99' Mustang GT 4.6L
88' F-250 Superduty 4x4 351/c6
95' Mercury Cougar 4.6L V-8
80' E-350 300/6 with a
3 spd column shifter. Top speed is 65mph, Go Baby Go!
I don't know about that fuel thing I just downshift if i need to stop i hardly use brakes unless i need to. I really don't care about MPG since i know its a hog and i pay to drive it.
Yeah, you're definately using fuel when engine braking. The EFI reacts to either engine vacuum or by metering the amount of air that it pumps, and mixes fuel accordingly. When you use the engine to slow down, the engine vacuum soars, the ignition timing goes to maximum vacuum advance (if equipped), resulting in a good, clean combustion. You'll use fuel doing it, but not nearly as much as using the engine to accelerate the vehicle.
'77 F100, 302 (the aftermarket Prodigy), C4
Cadet Second Lieutenant John F. Daly III
South Carolina Corps of Cadets, The Citadel
The TorqueKing
Right thanks TK, you def do use a lot of fuel while accelerating. I never use my engine to slow me down unless I am in 1st or 2nd simply because 3+ doesn't slow me down. I figure save the gas and engine wear vs a couple brake pads.
Primary rig is Green Thunder:
95' F-150 XLT 4x4, 302, 5 spd, MSD 6A, Sunroof, CD player with 2 10" subs and some 32" BFG Muds .
Check out my Gallery for a look-see.
Then theres:
99' Mustang GT 4.6L
88' F-250 Superduty 4x4 351/c6
95' Mercury Cougar 4.6L V-8
80' E-350 300/6 with a
3 spd column shifter. Top speed is 65mph, Go Baby Go!
Yup, minus the extra clutch wear from downshifting. My dad wasn't happy that i was right and he was wrong haha. He knows we're right but, hes stubborn and says he disagrees. Then he says ok you drive the way you do and I drive the way I do. He'd never say anything like that if he knew he was right haha.
Primary rig is Green Thunder:
95' F-150 XLT 4x4, 302, 5 spd, MSD 6A, Sunroof, CD player with 2 10" subs and some 32" BFG Muds .
Check out my Gallery for a look-see.
Then theres:
99' Mustang GT 4.6L
88' F-250 Superduty 4x4 351/c6
95' Mercury Cougar 4.6L V-8
80' E-350 300/6 with a
3 spd column shifter. Top speed is 65mph, Go Baby Go!