how does eec iv know piston #1?

[RonD]

Think of a carburetor, air/fuel mix is there for all cylinders at all times, batch fire is one step up from that.
All the fuel gets used, at idle, 600 RPM, 300 compete cycles(4-stroke), each cylinder's intake valve opens 50 times a minute, so almost once a second, at 1,200 RPMs it would be twice a second, the fuel gets used

 

[whitebroncoii87]

sounds like spray 3 times fire 1 time. ok if that's the way it is, that's the way it is. would be silly if one of those cylinders is in exhaust stroke while injector goes spraying. well, like my friend would say: this is a rich country.

 

[RonD]

But the O2 sees if the burn is lean or rich, so think of it this way, the injector opens 3 times but only adds 1/3 the fuel needed each time, so on the 3rd opening that cylinder is on intake stroke so gets the correct amount of air/fuel.
Next cylinder the same, and again and again, so no wasted fuel at all.

On startup the first few cylinders don't fire because not enough fuel, so it takes at least 2 revolutions for engine to start, then all is well

 

[adsm08]

sounds like spray 3 times fire 1 time. ok if that's the way it is, that's the way it is. would be silly if one of those cylinders is in exhaust stroke while injector goes spraying. well, like my friend would say: this is a rich country.

Why does it matter if the cylinder is on the exhaust stroke? You won't blow that fuel out the exhaust because it doesn't just magically pass through the closed intake valve while the cylinder evacuates the exhaust.

And it was done that way, 30 years ago, not because this is a rich country and we can afford to waste lots of fuel, but because this is what the technology was limited to back then. This was ground-breaking and revolutionary then. This is literally the first iteration of modern multi-port electronic fuel injection. You are comparing this system to what you would find on a vehicle built new in the last 10 years, there is just no comparison. That's the equivalent of pitting a 90 year old man with hip problems against a 15 year old athlete in a foot race and wondering why the old man looses.

 

[whitebroncoii87]

oh yeah, i was thinking about that last night in my sleep that it should not escape out of exhaust because those chambers and isolated. cool, had a nice sleep, ha. I'm not into new technologies just not a big fan of waste.

 

[alwaysFlOoReD]

I'm glad that this forum has the people it does. A person to ask the questions I've thought about but never asked. And people that can answer in a way that is simple and clear and will come back and clear up misconceptions.
I learned a lot this morning.
Cheers to you all and a big thank-you!

 

[adsm08]

oh yeah, i was thinking about that last night in my sleep that it should not escape out of exhaust because those chambers and isolated. cool, had a nice sleep, ha. I'm not into new technologies just not a big fan of waste.

I'm not a big fan of waste either. You should see my drawer of wire scraps and light bulb holders.

Even with a batch fire system there really isn't any waste. Like I said, when the 4.0 switched to sequential fire injectors it lost MPG. Kinda seems to me like SEFI might be the worse system.

 

[enjr44]

Yep, it isn't anything like a diesel where it is injected directly into the cylinder.

 

[gw33gp]

I think that may be part of the misunderstanding. The injector fires into the intake runners, not the cylinder with a batch fire system. So, cylinder doesn't get the fuel/air mixture until its intake valve opens.

 

[adsm08]

I think that may be part of the misunderstanding. The injector fires into the intake runners, not the cylinder with a batch fire system. So, cylinder doesn't get the fuel/air mixture until its intake valve opens.

This is a very good point, that I never considered relative to this discussion.

Up until very recently, I think starting in 2010 or 2011, all of Ford's gas engines were ported injection, which means the injector sticks into the intake manifold, just about an inch or so in front of the intake valve.

Then in 2010 Ford brought back the Taurus SHO, in 2011 they introduced the Ecoboost F-150, which both have the same engine. It is a 3.5L twin turbo with direct injection. In 2012 when they switched the body of the Focus up they gave it a 2.0L naturally aspirated DI engine. This means on those engines the fuel injector sticks right down in the cylinder and makes a V shape with the spark plug.