Unsafe throttle response when using cruise control?

Does your pathfinder have 2 OD gears?

Fyi the Tacoma has been drive by wire since 2002.

In the Tacoma you're probably cruising in 6th or possibly 5th so in order for the acceleration you want to feel on demand you're going to have to press quite a bit on the pedal to bump up the revs and get into the higher torque.

Or you can just disengage cruise, resume control of the throttle and pass what you need to.

Like it or not it's how the truck you and I bought operates.

 

You know he doesn't.

 

Throttle by wire has been on Tacoma's since around 2002 or 2003.

 

That was exactly what I envisioned when I read the 1st post, he is cruising along under 2000 RPMs and then barely touching the throttle expecting it to jump.

 

I thought that too. Then I read how he said all of our trucks are trash and he's some QA engineer so he's smarter than us and understands stuff. I then realized I didn't fucking care if he figured it out.

 

If you mean a cable between the pedal to the throttle body to mechanically pull it, yeah, but there was no electronic connection involved on my 2002 Tacoma- it went direct.

 

My 04 is throttle by wire.

 

QA guy... don't put engineer in there...

 

Yep, big difference.

 

I have a 2016 and kind like TFly said, it's a different truck to drive afterwards. Haven't run the 91 octane since it's about 60 cents a gallon higher around here, but even on the 87 version, it's a good drive now

 

My last car was throttle cable, one cable for the gas pedal and one going to the CC box. It was set up so the gas pedal moved both linkages, but the cruise could work independently when your foot was off the gas. If the cruise was on you had to press the gas down until it caught up to the position the CC box was holding at before it would accelerate more.

 

This behavior is 'normal' when taking over from cruise (at least mine does the same). You slowly start moving faster then "HOLY SHIT" you are going warp speed. These 3.5 motors seem gutless until you hit that powerband. Not what you expect at all, so I agree it is a tad unsafe. Somewhat similar to the OP, I was going up a hill in cruise control on a 2-lane highway, and went to pass a car and had the same experience. I was barely passing the vehicle until I pressed the pedal little bit extra and suddenly the truck accelerated so hard I swear I lifted a front wheel from the torque twist.

I expect it now, so it no longer bothers me.

 

Every car I have owned has does this or at least what I can remember. Including my multiple Mitsuishi's, my 96 4runner, and wifes Tacoma.

 

I think he also doesn't realize that Toyota chose a very nonlinear mapping of throttle pedal position to torque commanded. Increases very slowly at initial pedal deflection, and increases rapidly at near full pedal. Very different from mechanical throttle plate, which does very little for last 10 deg or so.

(Think Airbus, they love nonlinear responses to control input, especially that vary with control law mode)

 

Am I missing something here?

Misfires seem to be something completely different and unrelated?

 

Naw OP just gonna throw in all the buzz words to get someone to take his side.

 

I haven't read the entire thread, but the way the cruise control works in the Tacoma is the way it works in all other Toyota/Lexus/Scion models for as long as they have had cruise control. There have obviously been different implementations over the years and as a result it can feel differently under your foot, but the concept is always the same.

You set cruise control to 60 mph and take your foot off of the pedal. The cruise control system now has control of the throttle, and will apply it as needed to maintain that speed. If, on flat ground, it requires 50% throttle pedal equivalence to maintain that speed, you will need to press the pedal beyond 50% to increase the speed of the vehicle. Pedal travel between 0% and 50% will have no effect on the speed of the vehicle. If you want to have a significant increase in acceleration, you will need to push the throttle well beyond 50%. Again, this is how cruise control systems have always worked.

The functional application of this system can mean that you get one of 3 types of pedal feel while cruise is operating.

1. Conventional throttle cable, with the cruise control actuator acting on the throttle body: During cruise operation, the pedal in the vehicle stays in the depressed position (comes all the way up to zero), if you want to apply throttle beyond what the cruise control is applying, the pedal will feel light to the point cruise control is applying it (0-50% in the above scenario) and then it will have the normal weight beyond that as you open the throttle further.
2. Conventional throttle cable, with the cruise control actuator acting on the pedal: During cruise operation, the pedal in the vehicle moves to the throttle position required by the cruise control to maintain speed. If it requires 50% throttle, the pedal will move down to 50% throttle. You can apply more throttle by pressing the pedal further. The pedal will always have normal weight in this setup.
3. Drive by wire: Emulates Type 1 conventional operation, during cruise operation, the pedal in the vehicle stays in the depressed position (comes all the way up to zero), if you want to apply the throttle beyond what the cruise control is applying, you will need to push it past where the cruise control is applying (0-50% in the above scenario). The pedal will have normal weight the entire time, and you will only feel the vehicle accelerate once you are past what the computer is applying.

Type 2 is extremely uncommon on Toyota models. Type 1 and 3 are typical, with type 3 being the only type currently used on all new models. The drive by wire setup is done that way to emulate the way that conventional cruise control systems worked and to ensure consistency in the way that vehicles drive. This is normal, and it sounds like what you are experiencing OP. As I said, all Toyota/Lexus/Scion cruise control systems work this way, and it has been that way for at least 40 years.

Additionally, there are other safety factors that make this the only way I am aware that all manufacturers (not just Toyota) have implemented cruise control with drive by wire. The pedal position should always mean the same thing, whether cruise control is applied or not. What you are asking for is that the pedal operates differently when cruise is applied versus when it is not set. That is a dangerous game and one that I don't see ever happening. I don't think you will find a vehicle on the market today that has cruise operating the way you want.

If you are experiencing something different than what I've described, you may have an issue with your truck, but it doesn't sound like you do to me.

Jeff

 

Let's not throw the baby out with the bath water now...

 

So I interviewed an application engineer last night for a position in our engineering group. 25 years experience, extremely bright and articulate, wears crocodile dundee hat (with teeth) and is driving Chevy Bolt. Socks didn't match. Shoes did thankfully.

 

To answer questions about older Tacomas, the Tacoma got Toyota's first generation drive-by-wire system in 2002 for the 2003 model year. It still used a throttle cable from the pedal to the throttle body, however, it did not move the throttle body (except in extremely rare cases when in limp mode). Rather, it moved a position sensor which fed that signal to the ECU, and then the ECU controlled the motor on the throttle body to actually control the throttle plate position (and for cruise control). For the 2005 model year, Toyota skipped over to their third generation drive-by-wire system which eliminated the mechanical throttle cable connection.

Jeff