2016 OVTune Tacoma 3.5L Manual Transmission / Engine ECU Reflash

What he said.

 

Regarding Rev hang. I'm 99 percent certain I've found what actually caused the hang ups, and can modify or disable it. When ready, I'll see whose up to test.
Regard DFCO, currently for DFCO I see a master enable bit (completely on, or completely off). A vehicle speed threshold for deactivation / activation when no throttle is applied, a rpm trigger limit, and few others.

So I think what people will want regarding DFCO is a modification to the VST, vehicle speed threshold (re-engauge fuel when under 12mph)

So triggering the limit lower is possible, but then idle feedback control may interfere.

Toyota DFCO is unlike other cars...

 

The magician at it again!

I'll test BTW

 

Why would it be speed based, is that how toyota implemented it? Why is it not RPM vs pressure? I realize you probably cant answer that but that is just an insane way of implementing it.

That being said I think completely disabling it would cause more issues then helping(stalling coming to a stop), but who knows. I think what most really want is to lower the activation point to something just above idle that way during decel you dont just randomly get kicked in the ass for no reason.

I always found hondatas implementation super easy to tune even with really large injectors: https://www.hondata.com/help/kmanager/index.html?advancedparameters.htm

As a side note Rev hang other then emissions is also sometimes added for people that shouldnt be driving a manual but are. It allows them more time to shift without having to slip the clutch as much to bring the fly wheel back up to input shaft speed.

Also as another side note, I live in NY. If no one is seriously willing or closer then I am to get you a MT truck to do some R&D on, I would be willing to take a trip down. I feel like you are half guessing on some of these changes because you simply cant test them, which cant be fun.

 

Yes toyotas DFCO is vehicle speed based and it doesn't make sense.

Rev hang, for at least part of it, or where the rpm will "hang" for a moment is from toyotas idle speed feedback control, which engages at a high rpm or below. Why? No idea but any time you let off above this rpm as the rpms fall, it opens throttle

 

I am not sure I would be happy with defco kicking back in/out under 12mph when negotiating a tricky descent off road and suddenly find myself free wheelin over the obstacle...

 

Definitely put me on the test list for that please and thank you, and THANK YOU for keeping at this!!

 

I don't know that vehicle speed is the answer to the DFCO dilemma. I think most (if not all) of the complaints are about what it does when you are low in the RPM band. You'll be coasting along and then it feels like you clutched in and away you go.

or maybe this isn't caused by DFCO at all and its some other fuckery from mr sweers

the 1000-2000 rpm range is quite wonky to say the least whether its in traffic or off road. its unpredictable and annoying

 

2019 MT :heavy breathing:

 

In any gear?

It may work slightly different for the MT. But vehicle speed is a control or DFCO.

There is also idle feedback control. So, throttle opens at a higher rpm (4000) but fuel is still off, then, fuel will kick back on before 1000 rpm (regardless of speed).
Then, a second factor, if truck is moving, implement fuel cut off speed threshold into the mix.

A possible solution is implementing ignition retard right at this threshold. I'll have to investigate and test further

 

I’ve definitely felt it in all gears

 

Ok thanks.

 

Yep i've had it occur in 1-4. I dont coast low enough in 5th and 6th usually.

 

same here.

 

Agreed !! Moving it higher or lower will only move the problem higher or lower especially lower as this will add more time delay to the tip in.
The problem you mentioned in 1000-2000rpm range (I beleave is idle to 2700rpm) is mixing of the DFCO with the REV HANG is where the inconsistency and wonky ness comes to play.

 

you mentioned the throttle being open with no fuel above 3000rpm.this is strange as the rev hang starts at approximately 2700rpm and lower.
is it possible this is something Toyota has implemented to reduce REV DROP.

 

Sounds to me like most of the problem with Rev hang and DFCO stems from the idle feed back control.

IMHO if my foot is off the throttle the throttle should be closed. Damn sure should not be open at 3-4K rpm.

 

is that true your the pioneer of the ADM?

 

As far as I know I was the first one to do it on a 3g Tacoma. Used a brake line elbow of of a ‘85 Toyota Hilux as a coupling.

 

Well then!! special thanks to you to for the best mod for the price on this truck.

This mod is a must for the average to serious manual driver.
After getting used to it,I am finally able to make repeatable smooth shifts for the first time on this truck.