2006_BLACK_GT

This interesting subject came up in another thread. Instead of continuing to jack that thread I will pose the question here: On DECELLERATION, does the fuel system shut down completly? Specifically, is ANY fuel supplied to the combustion chamber when you let off of the throttle completely?

Let's keep it a friendly discussion.


Check out this article from Ford:
http://media.ford.com/article_displa...ticle_id=28869

SilvrStang

I believe it does because when you left off the throttle injectors dont open up and the fuel doesnt come in. I think its just simple physics.

_Slowbra_

"most cars built since the 1990's can detect the condition when engine revs are higher than idle with a fully closed throttle; under these conditions, all current to the fuel injectors is stopped, and no fuel is injected. That means if your foot is off the gas while the car's in gear; you're not using any fuel."

thats out of this months Car and Driver where they are trying to dismiss and "fuel saving myths". I dont know if Ford jumped on that train in the '90s or not; but the article said that most cars have had technology to cut fuel injection upon deceleration.

Emanpimpster

That seems kind of hard to believe. I would think the amount would be substantially less but that it would still flow because the engines still moving. There's fuel when its idling. Idk if im completely offbase here...

_Slowbra_

idling is different than deceleration. the article said that when the throttle is closed and the engine revs are above idle, then the fuel is cutoff. at idle fuel cutoff is disabled, but the fuel flow is minimized.

2006_BLACK_GT

Does it simply cut off fuel or does the ignition cut out too? I guess there is no need to cut both. It is highly possible, the fuel gets cut off, but since the biggest technological advance in the mustangs has been the 6-disc cd changer and cup holders, I can't quite believe it yet.

2006_BLACK_GT

This is from the article in my first post.

"DEARBORN, Mich., Aug. 13, 2008 – The 2009 Ford Flex saves gas during normal slowdowns thanks to a new technology that temporarily interrupts fuel consumption while maintaining optimal engine operation and Ford’s best-in-class driveability. The Flex is the first Ford vehicle to use this fuel control system, which will be featured on most upcoming Ford Motor Company vehicles."

I don't know if mustangs just use a different system than the new Flex, but I read this to mean no other Fords have fuel cut off during decel. I have been wrong before according to my wife however.

_Slowbra_

I'm pretty sure almost all EFI cars have this cutoff, what the Flex uses is an entirely new system..... i thought. if FoMoCo was the only company that didnt have this cutoff in the '90s then I dont know why they are hyping it up in the Flex, like every other car company hasnt been doing it for almost 2 decades.

And i thought the "my color" choice in the S197's was the biggest technological advancement from Ford????

vanquish

how can the car run if there is no fuel being injected? It has to run off something right?

_Slowbra_

when a car is in gear above an idle RPM, the car's momentum will keep the cars engine turning...when the clutch is engaged, the car is shifted to neutral, or the RPMs drop below a certain predetermined level....cutoff is disabled and the fuel injectors start spraying again. Im not a Ford mechanic so I am speaking from a very generic point of view, so if someone knows better please add to the discussion. I am only writing what I believe is correct, so dont blast me if I'm wrong.