Help solve the throttle lag problem...Traction Control

Which to me makes sense, TCS is more about grip when accelerating and decelerating in a straight line. VSC factors in side to side movement as well IIRC.

 

agreed, I have to test it some more yet.

the TCS is easy to turn off and doest light up the dash as well which is nice.

 

My throttle lag is certainly the issue described in other threads and solely occurs when accelerating out of a rolling stop/deceleration where, I believe, the ECU thinks that the vehicle is stopping and goes into some sort of fuel economy state. The sudden call for throttle does not properly interrupt the process and so a call for power is delayed.

It does not always happen and is difficult to predict - turning off the TRAC/VSC did help with the 'spongey' feeling of the throttle interaction and improved the feel of the drive, but has not eliminated the 'dead throttle' occurrences which result in 1 to 3 seconds of zero throttle response.

 

ok cool, thanks for the clarification as we try and track the specific types.

turning off the TCS did not take away 100% of mine I dont think, but it certainly cut them down, Im still testing.

I may do a neg terminal pull and see what that does as well at some point.

 

Without driving a Tundra, the rolling stop thing sounds similar to how my wife’s RAV4 operates. I think it’s poor transmission programming where Toyota holds gear 2 too long when down shifting. Usually at rolling speeds, at least in the RAV4, I can sometimes catch it in a “not as responsive” state because it’s finally (slowly and clunkily) finding its way to gear 1. Sometimes the RAV4 will be at a complete stop and it’ll lurch as it downshifts into 1.

I’m aware it’s RAV4 8-speed vs Tundra 10-speed, but from what I’ve read 2-1 downshift on any modern Toyota regardless of transmission is just abysmal.

 

IME, doing this for about 30 mins. has helped me in the past with other vehicles having this issue. Any adaptive learning in the ECU gets cleared out. Ever since drive by wire throttle has become mainstream on vehicles, this is a somewhat common issue. My old Mini Cooper S years ago was horrible at times.

 

I hear ya - this isn't that; this isn't a gear mismatch, there is 0 power at the engine. No RPM movement, literally nothing, dead. 1-3 seconds of throttle depression with NOTHING, then suddenly the engine decides to give power and it smoothly (albeit very abrubtly) accelerates very quickly. It's not jerky, its not the transmission slamming into gear at higher rpms - the engine is just sitting there enjoying some time off. I drove a stick shift for a long time, so I'm familiar with what a missed downshift feels like too.

 

I'm very interested to see if the battery disconnect, and perhaps a little more gentle driving style during the re-learning period, has any affect.

I've often wondered if the reason some trucks have the dead pedal lag and others don't is due to driving style during the learning period. I don't think I've ever done a full throttle launch, or even close to it, in my truck, and I've never experienced the lag. I don't granny it, but I don't get froggy with it either.

Now, with my old Jeep CJ, with a warmed over 360 V8, I like getting froggy with it. It can be a wild ride when I spin tires thru 3 gears in it.

 

That I experienced on a 2025 Hybrid 4Runner I test drove, but it was at a complete stop vs rolling. No motive power at all, not even from the hybrid system.

 

On some motorcycles

As well as disconnecting the battery, you can also short both cables together, positive to negative. Obviously while both are disconnected from the battery! This will ensure all stored current etc. is discharged from capacitors etc. Do your own research on this and an alternative is to leave the negative terminal off overnight.

 

I've read that 30 minutes of disconnected battery will reset the ECUs on these trucks. Maybe our resident Toyota tech @auaq can confirm.

My question is, when you do this, do you have to re-do all the memory presets, app, profile, and FOB linking, etc....? That would suck.

 

No, it doesn't reset your settings or saved profiles even after a 30min hard reset. Only radio presets, memory seats, and few miscellaneous settings will go away, but don't think your profiles and few other things on the radio head unit shouldn't go away.

 

will the 30 min reset the TCM as well?

 

To properly reset you would need to disconnect negative battery terminal overnight(8hrs). 30min isnt long enough.

 

Either that, or have someone with GTS+ reset learned values per TIS.

 

I think you’re on to something here. I’ve had so many occasions with this rolling stop then a good second or 2 lag and then sudden acceleration. It’s especially scary when coming into moving traffic. Always get the glare from the wife, thinking it was me.

I throw mine into S mode a lot going down hill, and I’ve seen some improvement with the rolling stop lag if I can shift it to 1st early enough. Also noticed it doesn’t like shifting into 1st gear unless you are moving very slow.

Going to keep testing this though.

 

i would think that if the transmission holds 2nd too long, timing of pedal press requiring acceleration and transmission mid shift to 1st would indeed cause a lag.

 

you arent shifting with the "s" mode, its only setting a gear limit.

 

Im believing more each day this magnuson has improved the acceleration from stop !!!

 

Yes. setting the upper limit, but lowering it forces it to downshift. Unless you hit an RPM limit for the lower gear, it will beep at you and refuse. I am aware and understand the difference.

With that, let me rephrase. If i can set the limit in S mode to 1 within the narrow window of RPM limit for 1st gear and before i need to accelerate from a rolling stop (for whatever traffic reason) its appears to help with the lag. just remember to “shift” and raise the limit or shift out of S mode otherwise you quickly redline in 1st.

 

cool, just wanted to make sure, so many people think they are rowing through gears, lol.

Ill monkey around with that too and see if I see anything

 

just overall acceleration or throttle lag surge?

 

From my stop and those hard right turn. Even with sport turned off. I dont have a pause in the throttle after I turn right.

 

Sorry, I don't follow aftermarket parts. Exactly what is the "magnuson"?

 

Please try to keep up with your own thread...

 

Thanks, I still don't know exactly what a "air charger cooler" is or does. Or how it could help with the dead pedal throttle lag, but that's cool that you think it helps.

 

The air cooler right before the throttle body. Big piece of metal under the engine cover. It's just larger.

 

After seeing this thread I’ve been driving with my traction control 100% off for a week and I will agree that the truck drives so much better. No lag, no clunky slow roll from stop, acceleration is smooth through the gears, throttle response is good. I have replaced my motor and I thought that was a big change but this traction off is something too.

 

ALL - See new TSB for throttle lag > https://www.tundras.com/threads/another-throttle-lag-tsb-will-this-one-fix-it.171410/

 

I’ve been driving with TC off since April 14 and noticed it drives better with less hesitation