In this day and age, when a “coupe” often means a four-door SUV and automatics, DCTs, and CVTs perform almost all gear-shifting duties, it’s nice to see a patent from a major mainstream automaker concerning a manual transmission.
However, Toyota’s recent patent for an electronic tranny nanny might spark worry that the three-pedal experience, as endangered as it is, could become watered down by technology. A manual transmission that doesn’t let you make mistakes? Who’s in charge here?
The patent, filed to the U.S. Patent and Trademark Office back in January (and first noticed by Motor1), concerns an electronic control unit for your stick-shift gearbox.
Automated manuals aren’t anything new, but making a manual tranny shift like an automatic isn’t this technology’s intent — at least, not entirely. No, Toyota’s patent fully recognizes the need for a clutch pedal, though the automaker clearly doesn’t trust the person behind the hand on the gearshift.
The controller’s operation seemingly has two functions: eking out better gas mileage by automatically shifting to neutral when the vehicle is coasting, and preventing the driver from acting stupid and potentially damaging the vehicle (or his pride).
It’s a very wordy patent, which you can peruse yourself. The gist, which comes by way of the application’s abstract, sums it up:
An electronic control unit permits a shift operation to a neutral position, by which a manual transmission 14 is switched to neutral, during coasting control. Accordingly, shifting to the neutral position can be performed only by the shift operation. Thus, power transmission can be blocked after termination of the coasting control. In addition, the electronic control unit prohibits the shift operation to a particular gear after the transmission is switched to neutral. Thus, overreving or underreving at the termination of the coasting control can be suppressed.
The patent filing goes on to describe how the car’s new nanny engages the clutch and places the vehicle in neutral to bring engine speeds down during coasting, while preventing the shifting of gears during this coast phase via lock pins. Should someone depress the clutch pedal during this phase, the system cancels and hands transmission management back over to the driver.
What gear the car ends up in following this phase depends on vehicle speed. Regardless, assuming the ECU works, it’ll be the right gear.
That’s because once the ECU terminates the coast phase, the same lock pins prevent the driver from selecting too high or low of a gear — potentially sending the engine past redline or bogging down. More MPGs and less powertrain danger is this invention’s goal.
Still, the question everyone’s asking is, “Why bother?” With clutchless transmissions more prevalent than ever before, why go to the trouble of smoothing out the longstanding drawbacks of the manual tranny? Also, if the ECU’s goal is optimum operation of the gearbox, what gears (especially lower gears) can drivers expect to find off-limits at any given time?
Will Toyota have us all driving Miss Daisy?
As that horse from Ren and Stimpy would say, “No sir, I don’t like it!”
One of the reasons we coast to a stop is to get a little engine braking involved, dropping the tranny into neutral defeats this. It’s also illegal to coast in neutral in the U. S. state of Georgia, where I happen to live. How much fuel does an engine use when the throttle is closed anyway?
Having the transmission prohibit you from selecting an inappropriate gear is fine with me
I thought that the engine cut fuel while coasting in gear. Putting in neutral actually causes the engine to use more fuel. Perhaps I’m missing something because right now, I don’t see the “WHY”?
Going down hills in “Mexican Overdrive” is technically illegal in many states. California code 21710 as an example.
I still run that brand of ABS and traction control on my older trucks.
Exactly. This sounds dumb…answer to a question nobody asked.
I suspect it’s kind of a mixed bag to coast in neutral or engine brake in gear. You burn a bit of gas idling in neutral or you lose momentum from the engine braking. Practically all engines nowadays cut off fuel flow during trailing throttle (lift foot off gas pedal at high rpm… they shut off the fuel in this regime because it never burns properly, instead spitting partially burned and unburned fuel out the tailpipe- it makes a cool burble sound in sports cars but it’s bad for pollution). You lose less momentum if you’re in a higher gear, but if you do it too slow in a high gear then most cars bring the fuel flow back online just above idle, somewhere around 1500rpm.
I think you are correct as to fuel flow when coasting in neutral (a small amount to keep the engine at idle rpm) vs. letting off the accelerator in gear (no fuel flow). But they’re not equivalent.
Let’s say you determine that if you shift into neutral at a given speed you can coast to a complete stop right at a stop sign a half-mile ahead, using only the small amount of gas it takes to keep the engine at idle rpm. But if instead you let off the gas at the same spot at the same speed without shifting into neutral, engine braking would bring you to a stop before you reach the stop sign, and you would need to reapply the gas to complete the distance.
I don’t have any science to back me up, but it seems possible that the amount of gas used in reapplying power in the second scenario would exceed that used to keep the engine idling in the first. This raises the question of whether stop-start technology could be applied to shut off the engine completely while coasting in neutral, but that’s a whole other story.
I would think that playing with the electronic throttle could accomplish the same fuel savings with less fuss.
No pedal – closed throttle no fuel
Slight pedal – open throttle no fuel
Slightly more pedal – almost closed throttle fuel
Of course software would need some serious calibration to make it smooth but I think this would save the same miniscule fuel that shifting into neutral would save.
When the throttle is shut and the engine is coasting the pumping losses go up in the engine since it has to fight against a vacuum created as the engine works (although fuel usage is cut drastically I think accounting for very high instant average fuel economy when your coasting) in and of itself I doubt Toyota’s strategy will greatly improve economy but a few percent here and there always help until something like HCCI engines become more prevalent and really boost engine efficiency across the board.
21710. The driver of a motor vehicle when traveling on down grade upon any highway shall not coast with the gears of such vehicle in neutral.
(Enacted by Stats. 1959, Ch. 3.)
If Toyota sells a transmission that automatically shifts into neutral, they will be forcing their drivers to commit an illegal act. Their poorly translated patent abstract doesn’t explain what it does very well. What the heck is “coasting control”?
Why are they trying to fix something that ain’t broken?
My guess is to game the MPG system, and to avoid bonehead drivers from downshifting into 2nd instead of 4th.
Control of the vehicle’s dynamics is why people choose manual transmissions. Too bad so few drivers actually purchase them, or even know how much for fun driving can be.
Cutting off the fuel while coasting or slowing, will “stall” the engine unless the driver, WITH the proper “gear selection”, can keep the RPM at or above “idle”.
Can most drivers be trusted to get this right?? This is why “neutral” is better than “downshifting” which wastes fuel, at best.
From what I understand, “stick shift” cars don’t have a fuel “cut-off” for coasting. That wouldn’t be a good thing.
Along with fuel cut-off, automatics use the “lockup” feature of the torque converter, to keep the RPM at idle when coasting/decelerating.
DenverMike – Manuals have had fuel cut-off for throttle closed operation for a long time, probably once port fuel injection became common. I remember in my 1990 Mustang 5.0L (5MT) you could feel and hear the fuel come back on at around 1500 rpm as the car slowed. Push the clutch in at 1900 and the engine would not miss a beat as the fuel (and sound) came back before the engine slowed. I’m sure my 2000 Lincoln (5MT) cuts off the fuel but with the smaller engine (3.0L) and new electronics I can’t feel the fuel coming back in and with the quiet exhaust I can not hear it.
I never noticed it! I also have a ’90 Mustang 5.0 (3.73s, aftermarket upper/lower control arms, overdrive pulleys). Interesting…
Lift off the throttle at 3000 rpm in third gear. As the car slow you will feel the fuel come on at somewhere around 1500. I’m assuming you still have the transmission neutral switch and the clutch switch connected to your EEC-IV.
DenverMike
Not quite. An engine that is braking the car uses basically no fuel at all, while an idling motor certainly does, at rest or in motion. Downshifting prior to or instead of braking saves meaningful quantities of fuel. Downshifting to accelerate can save fuel (less accel time) as well as prevent engine damage (less high load lugging). If a driver Rev matches or the car does it for them (like all dct’s do) it allows this technique to be used without accelerating clutch wear meaningfully.
No car has a fuel cutoff while coasting in neutral, those cars are idling as if parked. The transmission can’t affect this. What the ecu can do is shutoff the engine entirely at speed if they have a hybrid back up for auxillary systems like lights, brakes and steering. The current cars that do this are hybrids as a result. I’ve seen it referred to as sailing mode, I think in relation to the jetta hybrid or a porche.
The only reason for this patent is to be able to offer a manual transmission paired with a hybrid drivetrain that forces the driver to take full advantage of the hybrid potential. They need to force it bc fuel evening test cycles don’t allow for non standard driver behavior. Toyota is right to go this route, it’s the only way to pair the two technologies in such a way that government testing procedures will allow them the marketable fuel economy benefits. I hope the implementation gets it right bc I certainly wouldn’t be comfortable in a manual car that unpredictably selected “none of the above”.
tedward, engine braking instead of coasting in neutral slows the car down sooner, which takes a little bit more gas a few or several seconds ago. The difference is probably not all that much fuel (a little bit compared to a little bit), and not enough that I would consider engine braking as a way of saving fuel in any measurable or meaningful amount.
Also, as long as the engine speed isn’t very close to idle (i.e. anything over about 1500rpm) then it’s not really possible to lug it or otherwise damage it with wide open throttle.
Great info, Thanks!!!
Jimc2
It does add up. More time decelerating with no fuel used is preferable to any amount of time coasting and then, wastefully, braking. Of course, coasting is preferable if it results in not having to accelerate more in the future, so to your point,the line is admittedly pretty thin. The thing is, we collectively and individually drive a ton of miles. It adds up, although commute geography will play a huge role in personal results.
There are more than a few data log proofs out there that show this if you want to look it up. Auto transmissions are often setup to take advantage of this as well.
All that said I’m not telling anyone they should drive a certain way. One can drive safely and fuel efficiently using any reasonable driving style if they have a light foot.
Where do these people come from ?
The engine still runs – and uses fuel – whilst decelerating or when its in idle.
When decelerating there is more vacuum pressure so more fuel is used than in idle. EFI compensates for this but only partially.
The main issue is not consumption but emissions, which are greater because oil vapour from the sump is dragged up through the rings and the PCV system but there is insufficinet fuel vbeing delivered to burn all of it off.
Guitar man
Go and run your car downhill in gear with a high end scan tool plugged in, watch the fuel injector duty cycles. They go to zero (or effectively zero), with some exceptions for catalytic converter temp maintenance. This is never the case with idling. A very fuel efficient idle can run about half a liter per hour from what I remember, so it’s not a ton of fuel used, but the effect is obviously cumulative like all fuel efficiency discussions.
There are literally thousands of data log demonstrations online in easy Google reach. I saw this the first time while running data logs in a buddies project car years ago, but every enthusiast community online has had massive discussions on the topic.
“These people” indeed
I’ll take a regulated manual over an automatic and no manual option any day. And so we’ve come. Enthusiast are now like heroin-addicted hookers. Mmmmmm! Mmmmmmm! That’s so big! Give me more. Mmmm! You know it you non new car buying fucks.
How about Nissan’s slick “rev-matching” feature percolating to all the manuals?
Then we’d all look like heroes.
Good thing there not GM, they probably try to implement push button manual
GM has had rev matching for a number of years…perhaps the first, or one of the first. I find it a good tool to practice the appropriate rev matching speeds so you can do it yourself. Then again I don’t use the shift solely for braking purposes….why add wear to an expensive clutch when you have brakes for the purpose and they are cake to change….
BTW: they’re
If you match rev downshift properly, you add barely any wear and tear to the clutch AND you’ll always be in the right gear.
In a good downshift, your foot should let the clutch pedal back out noticeably faster than a normal first gear launch on level ground, and the engine should be within a few hundred rpm of the ideal speed (compare that few hundred difference with about 1000+ for a launch).
As an aside, a lot of people unwittingly abuse their clutches on launch too- those are the ones where you can hear the engine revving up to 2,000rpm or more and slowwwwwwly letting out the clutch. You should be able to smoothly launch a car in first gear with about a couple car lengths of roll and not much rpm above idle.
It was on the last Toyota Hilux I drove. The feature was optionally engaged by a button and it worked very well.
Or Corvette’s lockout of gears under less than full throttle…at least in the past.
Skip shift is still present…but you certainly don’t need anything like full throttle to avoid it. If you want it to go away, a simple $25 disconnect makes the lockout solenoid go to sleep….
The whole purposing of a manual is selecting gears myself! I often skip gears on upshifts when I know I’m going to be just cruising on level ground. And aggressive downshifts are one of the joys of stick shift driving. Having a manual “nanny” is nonsense. What manuals are left in Toyotas stable to apply this to? Base trucks? The GT86?
In the U. S, also Corolls SEs, Corolla IMs, and Yarises. In other markets, lots of choices.
I always skip gears going up. I generally shift Lincoln into 5th from 3rd, since 3rd is good for ~80mph and once I’m at cruising speed and done accelerating its into 5th. Same on a two lane pass. At 50mph I’ll drop from 5th to 3rd and go.
My motorcycle only allows 1 and 2 with the kickstand down, only 1, 2, and 3 while idling at a stop, no start with clutch engaged unless neutral, no start with kickstand down unless neutral. If it’s possible in a $5000 low end sportbike, its expected in a car.
Just because it is possible doesn’t mean it is desirable.
I think it should allow starting with the kickstand up in gear with the clutch engaged (how my old Suzuki works). Otherwise you are hunting for neutral after stalling at the light rather than just clutch, start, go (assuming you were in first to pull away and stalled it).
No start unless in neutral sounds like a bad idea. My goldwing f6b will start in any gear as long as the clutch is engaged. Having to be in neutral is how ones rolls backwards after they try to get the bike going up A somewhat steep hill.
I suspect this technology is more relevant to developing markets where manuals are more widely sold due to their lower price, and many drivers are inexperienced and poorly skilled. Anyone with bad driving skills in the US is likely to just buy the automatic (if a manual is even offered), so as to have more time available for texting, checking Facebook, and other important drive-time activities.
It could also guarantee that, unless specifically overridden, the car uses the gearbox “optimally,” as far as silly CAFE like mileage (and similar emissions…) tests go.
Keeping manuals safe, in an ever more hostile world, so to speak.
The feel-and-sensation attuned brainiacs at Toyota, have undoubtedly recognized that in the real world, the added visceralness, and increased need to work a bit for speed, inherent to manuals, result in them being driven in a manner that ends up more frugal than their “stomp on the gas and let traction control sort it out at every stoplight” automatic brethren. And hence that manuals are worth saving, even if one disregards driving pleasure for it’s own sake.
Most automatics get better EPA MPG ratings than the manual versions these days, and that is all the manufacturers care about. If you want to drive it like you stole it – just means you will be back for another that much sooner.
This,
Yesterday I was behind a CUV at an intersection where an accident had transpired literally a minute earlier. The police were there but, no tow trucks or EMS. The male driver ahead of me just camped there for about a minute after the light changed even though the police motioned him to proceed in a very animated way. I don’t know if he was snap chatting the scene or yanking on his male parts, but seemed totally oblivious to the external events going on.
This Toyota manual shifting technology would be appropriate for someone like this.
“This Toyota manual shifting technology would be appropriate for someone like this.”
I was thinking a foghorn, but OK.
Is the electronic tranny nanny an automatic that self-identifies as a manual transmission? Tee hee!
Does it have a pronoun?
“Also, if the ECU’s goal is optimum operation of the gearbox, what gears (especially lower gears) can drivers expect to find off-limits at any given time?”
I think it is safe to say this is simply a safe guard to prevent the operator from accidentally dropping the trans into 2nd gear while rolling along at freeway speeds. We have the CAFE cartel to thank for this one (again)
I dunno… in most manual transmissions I’ve driven you needed to push reeeeeeally hard on the gearshift to shift it into second gear at a speed anywhere approaching the engine’s redline, never mind faster. Unless the latest transmissions have super duper synchros nowadays and I just didn’t notice.
Granted, “you have to push really hard” isn’t a great safeguard… certain elements of the general public always find a way to bypass common sense and hurt themselves.
No, the money shift is quite easy to accomplish if you’re not paying close attention.
Super duper synchros I guess. Kids these days…
Any shift is easy if you match engine speed first.
Ah, correction- any shift is easy of you double clutch downshift to match the clutch and input shaft speed with the output shaft speed.
Very few manual transmission owners have a clue how to do this. There are a few layers above “manual transmission 101” here:
Downshifting- yes it is possible (101)
Match rev downshifting (201, and not actually necessary for a high speed downshift)
Double clutch downshifting (202)
The ones with fart can mufflers definitely do not- even the ones who have a slight notion about downshifting, I can hear them loudly riding their clutches halfway down the block…. and then coasting in neutral for the second half of the block.
I agree though- mechanically speaking and my hands and feet know how to make it happen. If I aggressively double clutch with the engine at, say, 5-6000rpm but the car moving at well past redline speed for second gear, I can force the gearbox into second gear without much physical effort if I quickly push on the shifter the moment I have the clutch back in, then if I dump the clutch voila, 8000rpm engine speed followed by a loud noise.
You can’t rev match for a second gear downshift at highway speed for most cars, the sychros are not good enough. I’m old enough to have driven clutchless after snapping a clutch linkage rod. Place it in first with the engine off, start and then shift up and down by matching speeds. Bit of a pain on Canal Street but that’s another story.
I think some of you guys might be mixing up match rev downshift for smoother clutch engagement with double clutching to enable smoother gear engagement.
The first thing matches the speed of the clutch and the flywheel. The second thing matches the speed of the transmission input shaft and output shaft for the gear ratio you wish to engage.
@pragmatic- I understand what you’re talking about (never had a broken clutch cable or clutch cylinder myself, but I did experiment and practice shifting without using my clutch), which is related to double clutch downshifting without disengaging the clutch.
For any manual transmission drivers who aren’t quite sure what I’m talking about, here is a trick question (sort of).
(1) Try this: get your car up to highway speed and in the proper gear for that speed, push in the clutch pedal and hold it there, and then attempt to engage first or second gear with the shifter. It’s a lot harder and maybe you have to push really really hard.
(2) Then try this- with the car at redline speed for second gear (this will be at a road speed a lot higher than the manual recommends shifting 2-3, probably about 50mph or maybe faster) and second gear engaged, dump your clutch.
The first “try this” illustrates why double clutching used to be a thing for non-synchronized transmissions or for cars with worn out synchronizers. The second thing illustrates why heel-and-toe match rev downshifting is a thing for smooth, quick downshifts.
JimC2 – Shifting into a too low gear even with double clutching and rev matching would meet noticeable resistance. Not saying it couldn’t inadvertently be done I just don’t usually force the lever that hard.
I had installed a T5 in my XR4Ti after the T9 died. The junkyard box had no sychros on 2nd and I did not feet like redoing the job for the 90 day warranty. Afterwards I needed to double clutch going 1-2 and double clutch and rev match for 3-2. I drove it this way for 100,000 miles. When I was selling it (with 280K on it). The buyer was trying to hamfist it into 2nd insisting it wouldn’t go in. I swapped seats and gave him a quick lesson in how to do it and sold him the car.
@pragmatic- I see what you meant now when you said, “You can’t rev match for a second gear downshift at highway speed for most cars, the sychros are not good enough [to get the shifter into the 2 position in the first place]”
“… would meet noticeable resistance. Not saying it couldn’t inadvertently be done I just don’t usually force the lever that hard.”
We’re both saying the same thing. I agree- maybe it could be done but you’d have to push really, really hard.
That’s a funny story about your gearbox and 2nd gear synchro. I totally understand it. Most people’s minds would be blown. Somebody must have really done a number on that second gear- usually the third gear synchro gets worn out most from rushed 2-3 shifts and people letting out the clutch a split second too soon before the gearbox is properly in third gear.
What? Do you understand the benefits of rev matching and how to do it?
Yes, as others have already stated, fuel pulse often drops to zero when coasting a manual transmission car. This is nothing new or groundbreaking.
But more importantly, when has anyone (other than the author of this article) referred to a 4-door SUV and a coupe? That’s just silly….
Seems like an attempt to improve fuel efficiency – which can only help Toyota to continue to offer manual transmissions. I’m in favour of it.
The list of cars they offer it in shrinks by the year though. :(
I don’t see the point. If I’m driving a manual, it’s because I want full control of the powertrain; including whether it is in neutral or the gear of my choice.
Nobody will be forced to buy it so it’s not really a threat to anyone’s freedom.
Also, since when have enthusiasts cared about Toyota?
Four-hole, 4/5-speed Toyotas are some of the best driver’s cars out there.
They put this in practice, and I will never buy another Toyota again, even auto
Do they understand any of the reasons why we like the last Supra?
Obviously not, that’s why they’ve involved BMW in the production of the next Supra.
Yeah so they can place BMW’s delay valves in the clutch line to limit drop speed. No wonder BMW stopped making manuals, make them crappy enough and demand disappears.
I think this is intended for a hybrid application. Either a current drivetrain or a future 48v system, doesn’t matter.
Reasoning. On a combustion only engine this would result in an increase in fuel use, by locking out engine braking which uses less fuel than idling. The only way this improves energy efficiency is if the system has regenerative braking which would convert light braking effort to usable energy for the batteries.
The addition of transmission lock outs is foolish however. They run a very real risk of not accounting for all driving styles and conditions in their software setup. I read the note about the clutch deactivating it, which should make Rev matching from the forced neutral possible, but I would still be concerned about the implementation of that. It’s literally not a problem that needs solving.
The jetty hybrid did this exact same thing, so the interesting part isn’t really new, just new to manual transmissions.
My guess is that it is for an automatic braking system with a manual – otherwise if the car would try to stop on its own the car would stall.