2016 OVTune Tacoma 3.5L Manual Transmission / Engine ECU Reflash

I don’t have a scanner, so no, I have not monitored. Only listen to my engine which since day one has purrrred like a kitten to the ear. Driven MTs for 32 years, but am not an expert on the tech side of things...

 

Lol. K.

 

Meh.

If it turns out Mat found something that benefits all of us, so much the better. You two are not going to convince each other with "facts".

At least this luminous guy has the tune, uses a scanner and data to back up his complaints and presents his arguments well. Much better than some ppl who just run their trap about the tune and don't have a clue (or the tune) lol.

 

Man! Here I was thinking about having a discussion about DFCO.

Oh well. =)

 

Hehe, for the good of all!

 

Discuss away brother, we're all on board with that one!

I personally don't want it nuked (I've seen that suggested on here), but rather altered so that it's not so intrusive when towing/off road. It does save gas though.

If we're going to nuke anything, it would be rev hang.

 

I can't really feel the misfires. My truck rides too rough for that. I mainly drive around in 5th unless it's really flat and I'm quick to down shift.

 

You kill me LOL

 

Talk talk OMG I thought I was alone on this issue .these guys don't understand the damage it causes

 

Here's my rambling about DFCO.

Way back in Post 441, I tossed in this graphic from my Torque app:
https://www.tacomaworld.com/threads...gine-ecu-reflash.515734/page-23#post-16413059

The gauge labeled throttle appears to be the actual throttle plate and the min / max marks seem to agree with what @luminous posted.

Since all EFI cars have DFCO, which I happen to like the principle of, I have never had a problem with it's function whether it is a slushbox or MT.

So, I am wondering if DFCO is the real problem or that the throttle plate hanging open at 17% while coasting is the real issue? When the fuel pops back on, the mixture at 17% throttle is going to feel a lot different than 3% throttle.

When I set up the EFI on my motorcycle after a service, the TPS is baselined at 0deg and the idle stop is set right around 3.5deg (3.9%). Of course, it doesn't have a DFCO function. I'm just using that as an angle reference.

Both the min and max throttle plate angles bother me for different reasons. I wonder what folks at altitude are seeing for min / max?

 

Wooh technical stuff
I'm more a feel guy.but are talking causes in jolts in drive train or something more technical

 

So if I understand correctly, you're saying that there could be an undesirably high volume of air flowing into the engine at the moment fuel injection begins again - causing a surge?
Hmm, I'll have to set up a PID to look at the throttle angle in various conditions.
I can tell you one thing though, the "closed" position for our V6 throttle butterfly seems to be 7 deg, if I'm reading this description of fail safe mode (read:limp) correctly:

 

Honest question, what damage are you speaking of?

 

psychological damage

 

For those who haven't been following the DFCO (Deceleration Fuel Cut Off) debate:

OVtune asked M/T owners to tell him some stuff they'd like to see from upcoming versions of the tune. Among the replies, altering or even removing DFCO was quite popular. Here's why:

Engine braking with V6 equipped trucks is not consistent. When you lift completely off the throttle (above a minimum RPM and possibly some other conditions), fuel is cut to the engine - it is not running, it's just being rotated by the drive line. As you slow down, and that magic minimum RPM is reached (approx 1300), the fuel comes back on. This dramatically and suddenly decreases the engine braking effect.

So why does it matter?

1. If you're towing a trailer and engine braking is helping you slow down, the sudden change at 1300 RPM can be at the very least annoying. I haven't towed with my truck yet, but others have noted their concerns in the past; and

2. When you are descending a steep hill off road and want to maintain control of your speed with the throttle, again, the sudden decrease in braking action is undesirable to say the least. Sometimes I want to be going slower than 1300RPM gives me in 4LO 1st gear, especially if there are rocks or other obstacles to traverse. Don't give me this crap about "just use your brakes" - I don't own a damn auto for a reason.

Anyway, one proposed solution was to lower the fuel cut in RPM to something closer to idle. We'll have to see what Mat comes up with, if it's even possible.

 

Yes. A large volume of air plus fuel to make the AFR match.

7deg sounds reasonable. I've had motors go into limp mode a couple times. Not a fun situation. Both acceleration and coasting did feel different. But, the last time was many years ago.

It would be good to see what you find. The TPS and throttle opening are standard functions, so you should be able to get the data easily.

 

took a break from here... sounds like I haven't missed much other than the usual internet noise

 

No. Just the feel of the engine braking, or the lack of it. I'm seeing a large throttle angle when coasting. Also, when I'm near a stop, I find myself getting on the brakes harder than I want.

 

In the scenario where I reach reach 1300RPM going down hill and slowing down (4LO 1st gear), it feels like you just took your foot off the brakes. It doesn't seem to accelerate or surge much.. no data to back it up, but hey OBD fusion has hundreds of PIDs to play with.

ARES32 and I both went into limp mode testing early 1.03 04B10 files, and I can attest to the fact that it is NOT fun. Personally I was being a dumbass, as I left my laptop at home after loading up the new file. Couldn't get more than about 40 KMH out of the truck and just getting the RPM up high enough to get it moving was a bastard. At least I wasn't far from home.

I'd like to hear more about your throttle angle hypothesis BTW, any other thoughts/data?