OFFICIAL: MY22+ Toyota Tundra - Throttle Lag/Hesitation From Stop Issue(s) - T-SB-0111-22

Yup. It's like a little go kart.

 

I’m gonna give this a shot down my street. I feel this is somewhere along the lines of what happened to me

 

I just had several recalls, temporary fixes and service campaigns completed 23TA03 (Tonneau Cover), 23TA09 (Fuel Tube), and 23TC06 (Parking Brake Flash) completed, in addition to new door seals. rlc177 I greatly appreciate your sharing the T-SB-0111-22 re: the pedal lag/hesitation/surge. I contacted my dealership and they indicated that this had already been reprogrammed during my recent flash. As suggested (thank you again ryanwgregg!) I used Carista to run my full ECU diagnostics. My Transmission Calibration ID is: 8A2100C03200. The new version is 8A2100C03400. Mine has not been reprogrammed yet. I reached out to the dealership again. Hopefully they will move forward with the flash shortly.

 

Yeah if you have 8A2100C03200, you are actually 2 revision behind, There should defiantly be improvements on the new calibration, however it may not fix all the problems you are having as us with the latest do observe issues.

 

Thank you Rkc177 and Ryanwgregg!
My numbers look like this:
Engine Calibration ID: 896630CR7201
Transmission Calibration ID: 8A2100C03200
Calibration ID: 895386002000

There are so many other calibration IDs! Insane amount of programming. Are there any other updates I should check on, to see if they need updating as well? Many thanks gentlemen

 

Yeah keep pounding the dealership about it, if there's another one nearby maybe call them they might have a different process and may help you easier.

When the tech connect GTS+ to the truck, there's a screen where it would show them that the software is out of date and when they even click on it it will bring up the exact tsb we are talking about.

But like I said write everything down and ask the service advisor to hand that to the tech, that why its not getting lost between changing hands. Sometimes I even go as far a printing out the tsb and leaving it on the seat so the tech sees it.

 

Look at all these TSBs!! I have a similar data dump from Carista. It will take me a long time to check every TSB and the calibration numbers to confirm whether every one has been updated.

I just had my truck in on Tuesday, they should have updated me to all the latest TSBs. I’m not impressed that they told me everything was up to date, until I checked Carista and realized my transmission is two updates behind. What is going on?

Will they also update the other TSBs while I’m in there next, or will I have to go through every TSB and print out instructions for the techs? Something is really wrong here.

 

Without going to deep in it. Toyota's "by the book" policy is that the tech is supposed to replicate the issue and match that to the tsb exactly and only update if that's the case.

Toyota instructs tech not to just "update to the latest code"

Most dealer if they can match your complaint to the tsb they just do it. Some follow the other process.

There are some risks in the process 1) you cannot revert to the previous cal if you don't like how it drives after. 2) if the dealer doesn't follow toyota process to the letter, Toyota may not re-embuse them for a bricked ECU that might need to be replaced.

 

I ended up burning a serious amount of rubber today due to this hesitation while looking at traffic barreling down on me....

I have nick-named my truck "LURCH"

 

A small displacement turbo engine at least revs when you touch the pedal. I've had a range of scenarios. Dead pedal at an intersection gets iffy, engine rev as if it's in 4th gear trying to take off at a yield/rolling stop,. Someone said to give it more gas at the rolling stop to prevent it but all that does is make it sound like a new manual shift driver slipping the clutch.

 

It doesn't quite fit the standard story, usually it wakes up after 2 seconds or so, but its similar.

However in terms of syncing issues it may be handy to note:

1) Time since starting the engine cold
2) Was the truck at a complete stop for a lengthy time
3) Approximate outdoor temperature.

 

VFTuner seems to be able to look at the Tables for the tundra's now so Hopefully there will be some insights as to what might be going on.

Some early observations seem to be the logic is VERY complex. Also Its been confirmed that there are MANY cases where throttle/power is severely limited, especially under 3500 RPM.

 

These "Load Control Tables" caught my eyes on the leaked info. You can see load is limited below 950RPM, which happens to be the rpm's were I see the most throttle limiting, noting also that RPM's getting above 900 RPM or so does seem like an "exit condition" in my data logs. The other load limit tables have very low numbers through mid rpm's as well. But I have no idea what each one represents yet.

 

I don't think what you experienced is exactly what the other have experienced, the concerning thing is any fault in the accelerator circuit should set a DTC and cause limp mode. If the ECU detects difference in its commanded throttle and the actual one it should also dtc and go into limp mode.

However the next time you see your dealer/advanced diagnostics person you can ask them to check "Vehicle Control History (RoB)" (Record of Behavior) for clues if anything weird happened.

 

I had my Transmission Calibration ID
TSB updated by two revisions yesterday from 8A2100C03200 to 8A2100C03400. There is an immediately noticeable difference in acceleration from stop and overall responsiveness and torque for me. Thank you all for letting me know about this. My dealership did not say anything about it until I specifically requested it and provided links and printout.

Much appreciated RLC177 and Ryan

 

Is there any hope that Toyota is working on a fix for this? I have the December 2022 update and it has now been over a year since this update. My dealer is telling me that this is the latest and there is nothing they can do. They have really not been much help. The worst part is, I switched from GM because of their terrible transmission programming only to end up with a truck doing the same thing.

 

I would say if no new calibration comes out by June/July time frame then its probably declared ok by Toyota. They tend to not really release new calibrations after 2 years.

 

A new TCU calibration is available as part of recall 24TA02 for the neutral issue. While that doesn't mention anything we are seeing, when Toyota issues a new Calibration, that supersedes any previous calibrations and as such can essentially address any previous TSB. It will be interesting after this cal is loaded we see a reduction of this issue.

The good thing being a recall everyone should be able to get it without much hassle.

At the very least the act of updating the CAL will reset the TCM Memory and start a relearn.

 

How long will it take NTHSA to update with range of VINs affected?

 

Documents show up on NHSTA within 3-5 days from submittal, but it should appear on your Toyota app right now if you are affected.

 

Any idea of when the dealerships will be able to start this process?

 

Thanks guys...looks like mine is good

 

Where did you get this? Load means mass air flow and is represented as a percentage of theoretical max NA flow at sea level from my understanding. So 100% means NA and over 100% means boosted. It’s not surprising to see ~100 at low rpm. I would love to see the other maps.

 

This was on a vftuner Facebook post. I'm not really a tuner and I don't ever mess with the fueling and timing etc. I have messed a bit with the request tables, throttle limit per gear and shift maps on 3rd gen Tacoma.

I have a vftuner license so I'm interested in at least looking though all the tables to see if there is any explanation of what might be going on. I did hear from a source that throttle is severely limited in many conditions including downshifts. It could be a simple as making a slight adjustment to the 1st gear downshift to a point that is a better match for my particular diving habit.

Unfortunately It looks like flashing will require a direct to ECU cable from what I can gather so I'm not sure if DYI tuning of this platform is going to be affordable.

 

I figured I'd start or add to a different thread when the VFtuner stuff became available to dig into things more. I'm going to try to get the new update next week and then do some new testing to verify if there is any change.

Mostly I'm pretty happy with the factory calibration except the uneasiness of not knowing if its going to respond consistently at rolling stops.

 

my lord, what the hell am I looking at there, lol.

 

I have the new calibration on my truck, will put it though the standard test on Saturday.

 

Preliminary results with TCU calibration 8A2100C03500:

Impressions: I was still able to feel the usual hesitation/roughness from going from a rolling stop. At no time though did the pedal feel dead or there was not response though.
So far I have not experienced any long dead pedal delays though but that condition doesn't always crop up even with test drives.

I did 2 drive cycles with logging running. I did note periods where I feet some hesitation. However when I looked though the data for every rolling stop I found that if I measured the delay from the time I press the accelerator before the throttle position sensor responded in a meaningful way, that delay now was always 312ms +- 15 ms (the polling rate fluctuates a bit between 115 and 125 ms)

I also noted most times there was a initial response from the throttle position pid but then goes back to zero for a bit. Throttle Duty ratio responds about 125 ms after the accelerator but doesn't increase in a meaningful way to move the throttle for about 275ms.

Keep in mid the "Throttle Position" pid is calculated at what the computer estimates the angle as. The actual movement of the throttle is done by manipulating the duty cycle PWM signal and the position sensor only responds with a voltage value. Very small throttle movements won't be picked up by the sensor pid.

I think this remaining delay/hesitation is more likely a ECU limit on the throttle not being enough to overcome the vehicle inertia at a rolling stop. The fact that the delay is very consistent now and not all over the place is promising. I would probably have to have a full month or so of trouble free driving though to kind of declare the 1-2 second dead pedal issue fixed though.

In short is probably best to get this update if you have issues right now but expect to still feel some delay.

Below were 3 different areas where the normal conditions for the delay seemed to exist but the delay calculated to basically 312ms every time.

 

@rlc177 - thanks for putting in the effort to collect, clean, and share useful data on behalf of the community.

Is it safe to assume your truck was in “normal” and not “eco” mode during these three logs?

 

Yes normal drive mode.