MT and DFCO

You're welcome!

 

Do any of the tunes implement dfco?

Seems like a way to squeek improvements in mpg

 

The 2.0 tunes revised DFCO in 2nd through 6th to be much lower. 1st was problematic and could only be dropped a couple hundred RPM. But, it is a noticable improvement.

No, though. My fuel flow questions were never answered, and the tunes do not change that.

I have kept offering to test new developments, but unfortunately, things are pretty silent regarding any 3rd Gen stuff.

 

I know on some bikes, depending on the mode, they will still feed some fuel depending on gear to avoid too harsh of engine braking. But as someone pointed out, the engine braking with the motor off doesn't change engine braking strength? Hard to believe, otherwise where is the fuel going.

 

What has not been considered in this thread is "Emissions". Just a grain of sand to throw out there, but I remember being told years ago that an un-firing engine with fuel going through it was putting out more emissions than a higher engine RPM. Just food for thought. Remember these trucks are just a bunch of compromises all compromising each other as that is what engineering is.

 

Yes, unburnt fuel is very bad for emissions.

The thing is most cars, and I'm pretty sure the Tacoma's with an automatic transmission, will completely shut off fueling when decelerating. So if the car is slowing and momentum can keep the engine spinning you might as well shut off the fuel and save that little bit.
Except the manual transmission Tacoma does not appear to do so. Which is strange.

 

I definitely see my MPGs increase when let’s say I’m coasting down a long hill in gear. DFCO works great.

Im on 94 octane 2.0 SFOB if that matters.

 

Mpg will increase, load has dropped so less fueling is needed,however it is still providing fuel.
Dfco however completely shuts off fueling so that NO fuel is provided to the engine, it is Nlnot doing this.

Mine lowers fueling when decelerating, it does not however completely shut off fuel like other cars (and AT Tacoma) do.

 

Why do you say it’s not DFCO?

I tried coasting in N vs in gear and the difference is there. I can also feel when DFCO shuts off and the fuel starts getting delivered.

 

I push pedal. Truck go. Whatever happens in between is voodoo.

 

Dfco is Deceleration Fuel Cut Off, fuel is completely shut off. In monitoring the fuel usage I can see the truck continues to use fuel whole decelerating, it does not cut off. It is reduced because there is no load, but it is still providing fuel. In essence the engine is still running. In most vehicles the fuel is completely cut off, no fuel, the engine stops running and momentum keeps the engine spinning.

Fuel flow should go to zero when in dfco. I have shown that not only is fuel still flowing it is flowing MORE fuel than if you had just put it into neutral, this is because rpm is higher than idle hence more fuel.

When decelerating in gear fuel usage is at least 3 times higher than just putting it in neutral

 

Just tested my AT, stopped it burns .25g/h; while going down a quite steep grade with my foot off the skinny pedal it was burning .40g/h in D.