MT - de-tuned throttle map when clutch is pressed in (disengaged)

[Deutsches_Sushi]

Okay, someone here was kind enough to provide me with their 2023 MT stock ROM.

Overall, when comparing to a 2023 Auto ROM, almost everything is identical. There are some scaling changes and obviously gear ratio changes and such. The throttle mapping for the 6MT maps are identical in both ROMs.

However, I did find these two tables that are pretty interesting. Obviously the clutch-in table is not used on a Auto Supra. This could be the table that flares the RPM up with the clutch switch.

Awesome find! Cheers!

Im wondering if its even worth a try to bypass "clutch-in" signal? for the mean time with a locked DME?
Also, does it compare to other neutrals too like gear neutral as a ( OR ) condition along with the clutch?

Have to check what connector they use from TE Connectivity if I decided to make a patch cable without splicing the existing one...

https://www.te.com/content/dam/te-com/documents/sensors/global/1308086-3-clutch-sensors.pdf

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[Mf1ve]

Awesome find! Cheers!

Im wondering if its even worth a try to bypass "clutch-in" signal? for the mean time with a locked DME?
Also, does it compare to other neutrals too like gear neutral as a ( OR ) condition along with the clutch?

Have to check what connector they use from TE Connectivity if I decided to make a patch cable without splicing the existing one...

https://www.te.com/content/dam/te-com/documents/sensors/global/1308086-3-clutch-sensors.pdf

Yes! A patch cable would be awesome anyway. We could put some logic probes on it and see what's going on, then interrupt signals and see the effects.

 

[razorlab]

The more I look at these tables the more I think they aren't what we are looking for. This is MAX RPM per speed.

I still think it's the neutral throttle mapping table I mentioned earlier in this thread.

 

[Mf1ve]

The more I look at these tables the more I think they aren't what we are looking for. This is MAX RPM per speed.

I still think it's the neutral throttle mapping table I mentioned earlier in this thread.

Fair enough. I think uncovering all the ways that the clutch sensor affects the ECU is important so thank you for exploring the data.

 

[zpower86]

I suspect Toyota/BMW originally designed the throttle mappings for the AT. It had the de-tuned mapping for "Neutral" which we are seeing. This is totally fine for an AT.

When the MT came out, they kept the mappings the same, applying the "Neutral" map to the clutch-in condition. Regardless, this is a design error by Toyota/BMW which hopefully will be fixed by the OEM!

I'm glad you all are digging into this!

 

[ColonelAdama]

Okay, someone here was kind enough to provide me with their 2023 MT stock ROM.

Overall, when comparing to a 2023 Auto ROM, almost everything is identical. There are some scaling changes and obviously gear ratio changes and such. The throttle mapping for the 6MT maps are identical in both ROMs.

However, I did find these two tables that are pretty interesting. Obviously the clutch-in table is not used on a Auto Supra. This could be the table that flares the RPM up with the clutch switch.

So nothing different on the cylinder fill/load tables?

with JB4, It seems like with AT cars it'll take cylinder fill >100% no problem and drop timing to maintain torque targets. MTs just panic and drop cylinder fill requests(dme boost targets)/slam throttle shut/etc. Maybe I don't understand it fully, but the way the ATs handle overfill is definitely different.

In other words, the AT cars adapt to boost overshoot and MTs do not.

 

[razorlab]

So nothing different on the cylinder fill/load tables?

with JB4, It seems like with AT cars it'll take cylinder fill >100% no problem and drop timing to maintain torque targets. MTs just panic and drop cylinder fill requests(dme boost targets)/slam throttle shut/etc. Maybe I don't understand it fully, but the way the ATs handle overfill is definitely different.

In other words, the AT cars adapt to boost overshoot and MTs do not.

Nope.

 

[Max3.0]

Nope.

Ever came to a solution to this?
Pretty annoying if you ask me!

 

[razorlab]

Ever came to a solution to this?
Pretty annoying if you ask me!

Solution to what?

 

[zpower86]

Solution to what?

A solution to make the throttle mapping the same regardless of the clutch position.

 

[razorlab]

A solution to make the throttle mapping the same regardless of the clutch position.

Oh, I don't own a manual so I don't really have any skin in this game.

 

[Max3.0]

Solution to what?

Oh ok, thought you owned a MT.
I have 3 manual cars and always had. The Supra is the only one that revs up like crazy when doing hard pulls and clutching in. Very weird behaviour and super annoying when you want to have quick shifts.

 

[swrdply400mrelay]

I don’t suppose this can tuned out with an unlock via MHD or BM3?

 

[DC5UPRA]

Oh ok, thought you owned a MT.
I have 3 manual cars and always had. The Supra is the only one that revs up like crazy when doing hard pulls and clutching in. Very weird behaviour and super annoying when you want to have quick shifts.

Weird dont have this issue, whether I was stock or on MHD. 8k miles now.

 

[Max3.0]

Weird dont have this issue, whether I was stock or on MHD. 8k miles now.

Doesn't do it all the time. If I concentrate enough to release throttle in advance perfectly (like compensate for the rev hang) than it's fine.

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