Is There A Fix For Auto Trans Wont Shift Into 4th Until Warm?

[41magmag41]

Originally Posted by bronsin

If the mod works I will have my cake and eat it too!

Eat the cake and have toyota laugh at you if you try to get work done under warranty, providing the car is still under warranty, because you mod it. m

[bronsin]

Fuel dilution happened in carbed engines that idled because the mixture was rich. With FI that is not the case. The mixture is correct.

You still have the problem of increased warmup time however if you idle. And of course if you aint moving youre losing.

Im hoping Scotts reisitor mod will prove feasable. I got 28 mpg at times this winter driving 6.5 miles to work.

Proof is in the pudding. Either it gets better with the mod or it doesnt.

But Im wondering if the 3rd gear thing is to warm up the TRANSMISSION not the engine?

[SAV912]

Isn't 3rd gear in the ATX at 45 MPH around 2500 or so RPM? Hardly WASTING fuel.

Truth is, Toyota designed it that way since it's such a small engine. The quicker it gets to operating temp, the quicker it reaches the most efficient temperature to operate at thus burning less fuel. There are many, many more factors you should be looking at if you're getting shit mileage in the winter (IE 28 MPG) before blaming it on the ATX not shifting into 4th within a mile or two of starting up. I guarantee you that mile of being stuck in 3rd will not net you the increase from 28 MPG to whatever you think you should be getting. Blame winter blend gas, underinflated or winter spec tires, or your short commute before you go modifying the electronics in the ATX.

Solution:
1. Trade for manual, although lugging the engine when cold won't do you any favors in regard to fuel efficiency.

2. Leave New Jersey.

-C

[41magmag41]

Originally Posted by SAV912

Isn't 3rd gear in the ATX at 45 MPH around 2500 or so RPM? Hardly WASTING fuel.

Truth is, Toyota designed it that way since it's such a small engine. The quicker it gets to operating temp, the quicker it reaches the most efficient temperature to operate at thus burning less fuel. There are many, many more factors you should be looking at if you're getting shit mileage in the winter (IE 28 MPG) before blaming it on the ATX not shifting into 4th within a mile or two of starting up. I guarantee you that mile of being stuck in 3rd will not net you the increase from 28 MPG to whatever you think you should be getting. Blame winter blend gas, underinflated or winter spec tires, or your short commute before you go modifying the electronics in the ATX.

Solution:
1. Trade for manual, although lugging the engine when cold won't do you any favors in regard to fuel efficiency.

2. Leave New Jersey.

-C

YAY plus one for some common sense. Econo cars why screw with them.

[bronsin]

Originally Posted by SAV912

Isn't 3rd gear in the ATX at 45 MPH around 2500 or so RPM? Hardly WASTING fuel.

-C

So...put your money where your mouth is and do me a little favor. Drive normally in 4th gear for a tank of gas and record your mileage. Probably you already know what your mileage is. Great! Now drive a tank of gas in 3rd gear. I would like to know what difference it makes. I would do it myself but thought you would be eager to prove me wrong.

[SAV912]

Originally Posted by bronsin

So...put your money where your mouth is and do me a little favor. Drive normally in 4th gear for a tank of gas and record your mileage. Probably you already know what your mileage is. Great! Now drive a tank of gas in 3rd gear. I would like to know what difference it makes. I would do it myself but thought you would be eager to prove me wrong.

No, I'm smart and bought the proper transmission (manual) for my driving style. I'm not the one starting with one thing and trying to turn it into another.

You asked a question, and you got an answer. It's nobody else's problem but your own if you're not satisfied with it. For what it's worth, I'm not in 5th until 40+ MPH anyway. I don't see why you're pissing and moaning about an automatic doing what it's suppose to do at low speeds and low temp/op conditions. The quicker the engine reaches optimal temp, the quicker it gets to max efficiency. Modifying the programming to get into 4th as quick as possible under cold conditions will result in it taking LONGER to reach optimal temp, and thus burning more fuel anyway, defeating the entire purpose. You got 28 MPG for a variety of other reasons. Not because you can't get into 4th for one mile of your seven mile commute.

-C

[41magmag41]

Originally Posted by SAV912

No, I'm smart and bought the proper transmission (manual) for my driving style. I'm not the one starting with one thing and trying to turn it into another.

You asked a question, and you got an answer. It's nobody else's problem but your own if you're not satisfied with it. For what it's worth, I'm not in 5th until 40+ MPH anyway. I don't see why you're pissing and moaning about an automatic doing what it's suppose to do at low speeds and low temp/op conditions. The quicker the engine reaches optimal temp, the quicker it gets to max efficiency. Modifying the programming to get into 4th as quick as possible under cold conditions will result in it taking LONGER to reach optimal temp, and thus burning more fuel anyway, defeating the entire purpose. You got 28 MPG for a variety of other reasons. Not because you can't get into 4th for one mile of your seven mile commute.

-C

Again Plus 1 for some common sense.

[bronsin]

Originally Posted by SAV912

No, I'm smart and bought the proper transmission (manual) for my driving style. I'm not the one starting with one thing and trying to turn it into another.

You asked a question, and you got an answer. It's nobody else's problem but your own if you're not satisfied with it. For what it's worth, I'm not in 5th until 40+ MPH anyway. I don't see why you're pissing and moaning about an automatic doing what it's suppose to do at low speeds and low temp/op conditions. The quicker the engine reaches optimal temp, the quicker it gets to max efficiency. Modifying the programming to get into 4th as quick as possible under cold conditions will result in it taking LONGER to reach optimal temp, and thus burning more fuel anyway, defeating the entire purpose. You got 28 MPG for a variety of other reasons. Not because you can't get into 4th for one mile of your seven mile commute.

-C

Well maybe I can get YOU to put your money where your mouth is. Drive for a tank of gas in fourth gear of your manual trnasmission and tell us what mileage you get.
We trust you to tell the truth!

If this mod proves possible I will post my results also. Then we will see what is what.

[SAV912]

Dude, you're just not making too much sense. People with manuals such as myself CAN get into 5th gear right away with the cold lamp activated, but it is certainly not beneficial in regards to fuel economy. Since the ATX does the shifting for you, it automatically (imagine that?) figures the most optimal gear to be in under the given conditions. And in the conditions under a cold start, it is optimal to get to optimal temp as quick as possible, hence locking out overdrive.

Originally Posted by bronsin

Well maybe I can get YOU to put your money where your mouth is. Drive for a tank of gas in fourth gear of your manual trnasmission and tell us what mileage you get.
We trust you to tell the truth!

If this mod proves possible I will post my results also. Then we will see what is what.

I'll tell you the truth right now. That's not the same situation as what you're proposing. You don't take off from stops in 4th gear of your ATX, why should I do it with an MTX and post the findings? You also don't know my driving conditions or my commute. From what you posted, you'd actually be pretty alright cruising in 4th gear of the MTX at 40 MPH. If you had my commute which involves several miles down I-95 in 80 MPH flow, then I'd be first in line to tell you that you're silly for staying in 4th at that speed, but that wouldn't be applicable either as by the time you reach the highway from where I live, your ATX would've warmed up and you'd be fine. Drop to overdrive immediately from a cold start, and that may no longer be the case, thus keeping the engine colder longer and not optimally efficient thus robbing you of more fuel economy than if you let the transmission do it's job. I don't know what better way to explain it to you, but go ahead and for shits and giggles, do your mod. Report back the findings. You're already sitting right at the EPA City rating for the Yaris, so I don't know what more you expect to find given your commute, conditions, and driving style.

It's almost comical how some of the fuel economy guys think they know better than a corporation full of engineers.

-C

[sbergman27]

Originally Posted by SAV912

Truth is, Toyota designed it that way since it's such a small engine. The quicker it gets to operating temp, the quicker it reaches the most efficient temperature to operate at thus burning less fuel.

I've never been quite sure *why* it's designed this way. Whether its a cold engine drivability thing, an emissions thing, a fuel economy thing, or an engine wear thing.

But it makes no sense to me that a higher engine speed is going to result in faster warm up. Assuming the driver is calling for the same road speeds and acceleration, the 3rd gear scenario is going to have a lower torque and faster rpm. The 4th gear scenario is going to have higher torque and lower rpm. But the overall power (work / second, or force x distance / time) is going to be the same in each case.

My bet is that the lockouts are supposed to improve cold engine drivability.

-Steve

[bronsin]

I have the home made cruise control for $10 installed. They have never detected it. What makes you think theyre going to know about a modifyed coolant temperature sensor? They are too busy looking for power pulleys, aftermarket suspensions and turbos.

Let me guess. You guys are sitting on your couch all day playing video games.

[41magmag41]

Originally Posted by bronsin

I have the home made cruise control for $10 installed. They have never detected it. What makes you think theyre going to know about a modifyed coolant temperature sensor? They are too busy looking for power pulleys, aftermarket suspensions and turbos.

Let me guess. You guys are sitting on your couch all day playing video games.

actually no wise butt, driving a heavy dump all week and only check this in the evening or if I'm not working Saturday. butt enjoy your need for speed in the wee early mornings while your car tries to do what it's programed to do.

[MadMax]

There is no "fix" as there's nothing wrong with your transmission! It was designed to stay out of fourth gear until the engine has reached a certain operating temperature. It is for your engine's benefit and it would be detrimental to try to override the function.

[bronsin]

Originally Posted by MadMax

There is no "fix" as there's nothing wrong with your transmission! It was designed to stay out of fourth gear until the engine has reached a certain operating temperature. It is for your engine's benefit and it would be detrimental to try to override the function.

Why would it be detrimental to the engine? A manual can be shifted into fifth immediately. Are people with manual transmissions having problems with their engines.

[MadMax]

Originally Posted by bronsin

Why would it be detrimental to the engine? A manual can be shifted into fifth immediately. Are people with manual transmissions having problems with their engines.

Not yet, but if they're shifting into fifth gear with a cold engine they might be doing unknown damage. It's well known that it's not good to go into OD when an engine is cold, and our little Yaris is smart enough to prevent the transmission from doing so. Why people want to override this excellent feature is beyond me, I guess they think they are smarter than the engineers who designed and built it!

[bronsin]

Originally Posted by MadMax

Not yet, but if they're shifting into fifth gear with a cold engine they might be doing unknown damage. It's well known that it's not good to go into OD when an engine is cold, and our little Yaris is smart enough to prevent the transmission from doing so. Why people want to override this excellent feature is beyond me, I guess they think they are smarter than the engineers who designed and built it!

I work with engineers who design proto type electronics for miitary and space applications. They design it I build it. Once we had 60 days to buiild the 150 circuit boards that went into a data recorder for a satilite. They put a software engineer in charge of the machine that built the boards. Under his direction they built 4 or 5 boards A WEEK. Because we would never get done in a year at that rate they put me running the machine on second shift. My first night on the job I built 14 boards all by myself. QC went apeshit in the morning. They thought they were all screwedup. Wrong.

When we went to surface mount electronic in 1994 the freaking genius engineers degreed we could not add flux to the parts before soldering. There is flux inside a hollow core and they said that was specifically designed by engineers whose shit does not stink to be all that was required. We assemblers were agast and just added it anyways. When some of us were punished for that we came to the realization we could screw them over by doing what they told us to do. The quality of the work was so bad they recinded their edit in a month.

That is the side of engineers you never hear about.

[sbergman27]

Originally Posted by MadMax

It's well known that it's not good to go into OD when an engine is cold

If I had a nickel for every "well known" bit of wisdom I've heard that turned out to be totally baseless, I'd be rich. So with my skeptic's hat on, I'll ask "how do we know this?". What evidence (as opposed to hearsay) can we point to?

I suppose what it boils down to is a assertion that a cold engines handle higher RPMs better than they handle higher torque, with respect to wear.

My Yaris is A/T. But my Chevy Sprint ER is a 5 spd manual. When cold, I shift at about the same points as I do when warmed up, getting into 5th at about 45mph. It would be interesting to know for sure what strategy minimizes wear.

-Steve

[Astroman]

Wow two pages and no correct answer why the transmission is locked out of 4th. It has to do with emissions (the cats need to be at operating temperature to work properly) and the quickest way to get them up to temp is by running the engine at a higher RPM. If your not going over 45mph why are you so worried about not getting into 4th for that short of a commute? My car only takes a mile at 30mph to get up to operating temperature, even when we were in single digits. Stop and go, tires, conditions, winter gas and other habits have more effect than not being able to get into 4th at 45mph.