2016 OVTune Tacoma 3.5L Manual Transmission / Engine ECU Reflash

OK, welcome back smartass

Amusing ourselves while waiting for the next release lol

 

Tune file received, flashing now. One question for OVTuned,is this file the updated version with data from this past weeks Dyno Day?

 

Our volvo wagon was the last one to go into limp mode. The worst part was that it was still under warranty and wouldn't throw a code. I had to drive it around in limp mode for a while just to get it to store a code.

That is about all that I have at the moment. Just mainly that the large angle is what makes folks unhappy with DFCO. Getting a normal amount of engine braking would go a long way toward justifying a tune purchase for me.

 

If the file name doesn't have 103B in it, then it's doubtful.

LIST OF GOODIES UPCOMING IN 1.03B M/T and A/T IS UP OVER ON THE DEV THREAD!!! - POST 9404

 

Just got back from a test drive after the tune,you can definitely notice a difference in throttle response and low end power/torque increases. Roads were getting a little slick and it was hard to keep from breaking loose, it didn't do that before the tune unless I really got into the throttle. I will be out and about tomorrow after it warms up and the roads thaw out for more evaluation. So far I am impressed.

 

My SGII/Tacoma reports throttle in PERCENT. Maybe the 7 and 17 is an apples and oranges situation?

 

In any drive train you will have lash .the lower the tolerance as per manufacture design the more the lash. If you ever have your truck off ground and rowtate a tire back in forth it will rowtate 1in or more. This is collective play of every gear in trany u joints and rear end.
when decal kicks in,it will start from rear tire and move it's way up to clutch.
when on throttle it will start from clutch and work it's way to the last spline in axle.
This acts like a wip with a ton on ether end.add a trailer or another ton and the jolt multiplies.
In the heavy transport world this leads to twisted shafts broken pinion gears and short trany life.

While I can understand the short term feul and brake saving feature of DEFCO.i don't be leave it's worth the long term agravasion of altering a century old driving technique.
That's why never buy a vehicle off some one who treats the throttle like a on off switch.

 

I never noticed DEFCO kick in at that rpm,I will check it out,maybe that's why the gate stays open to allow air in to compression stroke with out combustion.this will allow more engine braking.this is how Diesel engine brakes work.
By lowering feul cut in you just moving the problem lower in the driving rang,this may benefit your driving habets but not others.

The only way I see OVTUNE can regulate DEFCO is to kick the ingectors in one at a time to make a smother transition but that sounds like a lot of RND.
I beleave killing the DEFCO is the easiest first step (after rev hang)as it is not part of engine design like the Atkinsons is.no risk to longevity of engine.
That is why I am pushing for a trial,that way guys can see just how much feul it saves than based on feed back OVTUNE can take further steps.

 

Oh crap! My mistake. I'm seeing 17% min and about 65% max. Shown in Post 441. 17% should be about 15.3deg.

 

Up to 65%!
If no air passes through throttle plates it will reduce air pressure in combustion stroke and reduce engine braking.this may be why your seeing any opening up of throttle plates on decel.(theory)
On heavy deasel engine braking when in decel,sensor will retard on top of compression stroke by opening exhaust valves,this will remove any down word pressure resulting in more resistance and load fart type noise.

 

@tonered , I think we need to monitor VVT angles during DFCO as well.. I'd be interested to see what's happening on the intake side. In theory, you'd think the best engine braking would result from high compression ratios (OTTO mode). Spitballing, of course.. but we should be able to see what's happening.

 

Disabling DFCO would absolutely kill full economy and also speed up wear of the cat due to extra unburned fuel flowing into them. Every modern car kills the injectors when off throttle so its not like this is something new. Why Toyota made theirs act this way is interesting and quite annoying.

Injectors dont like to start up with short pulses, its the most difficult condition for an injector which makes getting back on the throttle harder just due to the way injectors work. http://injectordynamics.com/wp-content/uploads/2013/12/LowPulseIDRange.gif

Now keep in mind at higher loads direct injection is being used, and at lower loads both direct and port injection are being used. This adds quite a bit of logic and complexity and I imagine that is why we are seeing what we are seeing. What im getting at is based on load, injector strategies may be flipping between DI only and DI and PI causing some of these inconsistencies. The below article explains how this works as well as explaining how other automakers (ford in the case) use a different strategy which always keeps both DI and PI strategies enabled just at different percentages based on load. This is a guess based on what i've felt personally, once I get the updated tune ill start looking into this a bit more as well.

https://blog.caranddriver.com/explained-why-some-engines-have-both-port-and-direct-injection/

 

I'm with you on not nuking DFCO completely.. that said, the way Toyota implemented it on this application is far less than optimal. What a surprise..

 

Engine braking is not free.the better the engine braking the more your engine works.you will be in save now pay later senario.engine braking becomes economical when hauling two or more times your weight and brake jobs cost 1000$ plus pr axle.
On my 4 banger sec gen I got 220 k on original pad and rotors.a trikal down effect from my days running transport.
Now I am targeting 100 to 120k that's more than enough.
So what I am saying is BRAKE!BRAKE!brake!

 

While I get what you're saying, I also don't want DFCO nuked completely. It does save gas in these trucks, that's a fact. I can see it in my trip average fuel economy every day. BTW, my top priority in this debate is not to save money on brake parts.. although that is a byproduct. I just want consistent engine braking in the scenarios I mentioned before.

 

I haven't seen anything in the Torque app that show VVT. Any clues there?

I haven't looked into the Carista app much either. There might be something in there?

I haven't looked at Fusion at all.

Good point about the faux Atkinson cycle. That probably works against engine braking and might be the reason for the 17% min?

 

I don't think it will kill feul economy but let's try.and if rev hang is killed it will compensate.as far as cats are conserned do we know that they last longer after intro of DEFCO

 

I think we are confusing exhaust braking (jake braking) with engine braking. Of course, the complex Taco motor doesn't make it easy.

On my motorcycle that has a simple open loop EFI and no DFCO, the throttle works like a brake being that it is a lumpy L-twin. Opening the throttle progressively kills engine braking. The effect is very linear. The engine braking on that machine is excellent. Most cars that I am following with be riding their brakes and I can slow faster than them. In normal riding about the only time I touch the brakes is to finish stopping after downshifting from 2nd.

I am not looking for that amount of braking with the Taco, just a usable amount.

Edit: as I said above, I never felt a problem with DFCO or engine braking in any previous car. Even our DiT Forester has great engine braking.

 

Cats were around while carbureted cars were still being made. They did ruin cats in short order, but they were open loop. A ruined cat had no feedback loop into the AFR.