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Discussion Starter · #1 · (Edited)
I did some more thinking on this this morning as I don't have much to do right now w/r to the COVID $hitshow going on. I wondered if you could log the accelerator/throttle %s without the car running which has obvious advantages. Well, you can! Here's a video of how to do it/what it looks like:

https://youtu.be/QryM1yG4UQk

I plotted up the data for each setting in the “driving profile switchover” adaptation under the steering control unit – “indirect, controlled over time” vs. “direct, controlled over threshold value” in my Golf Sportwagen. They are the same. This setting is not, based on these data, changing the ratio of the pedal to throttle as many say occurs.

Notes. Some have said that this is b/c I have a tune, some have said my car doesn’t get impacted by this change vs. say a GTI or R. I have showed how to log it so I am hoping others will do the same so we can see other data. What would be really cool is for someone to do this that has a pedal tuner box! I have posted a video previously showing what this change does, it changes the amount of time it takes to make changes to the steering setting when (and if your car has different drive modes) you change from normal to sport mode or back again.

https://www.youtube.com/watch?v=8jxsqdbrBrY&t=30s




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Yeah Karst, I have to admit I am in your camp. Changing this on my '19 Alltrack S manual the other day did basically zilch. I have a very sensitive butt dyno as I have been modding and tuning all my cars for the last 20 years, and my daily job is dyno-testing engine performance for an auto supplier. And I can't say I noticed any benefit to changing this setting, even though I definitely hoped to get a bit more throttle response. Some people call it a total game changer? Made them love the car again? Sheesh. I also believe in the power of placebo, but I try to stay calibrated to receive real data in my brain.

People. This setting is in the steering module. If you think VW powertrain engineers are going to place accelerator pedal profile settings in the steering module, well, you're weird. Because they wouldn't.
 

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Discussion Starter · #3 ·
Yeah Karst, I have to admit I am in your camp. Changing this on my '19 Alltrack S manual the other day did basically zilch. I have a very sensitive butt dyno as I have been modding and tuning all my cars for the last 20 years, and my daily job is dyno-testing engine performance for an auto supplier. And I can't say I noticed any benefit to changing this setting, even though I definitely hoped to get a bit more throttle response. Some people call it a total game changer? Made them love the car again? Sheesh. I also believe in the power of placebo, but I try to stay calibrated to receive real data in my brain.

People. This setting is in the steering module. If you think VW powertrain engineers are going to place accelerator pedal profile settings in the steering module, well, you're weird. Because they wouldn't.
You and I can be friends after the apocalypse. ahaahah
 

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No, it doesn't affect the final throttle position at all. The default settings is an artificial time delay that's inserted to smooth your inputs and improve emissions and fuel economy. I found that with the time setting the GSW AT was often confused as to my intentions, especially in hilly terrain. After changing to the threshold setting the transmission actually seems to understand what I want and is significantly more responsive.


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No, it doesn't affect the final throttle position at all. The default settings is an artificial time delay that's inserted to smooth your inputs and improve emissions and fuel economy. I found that with the time setting the GSW AT was often confused as to my intentions, especially in hilly terrain. After changing to the threshold setting the transmission actually seems to understand what I want and is significantly more responsive.


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This

What you're logging would just be good for pedal box as the pedal box changes the input per position, i don't think the coding changes the input it changes the output.

Remember the throttle is just an input into the system the output is torque/accelerations. How the ECU interprets the inputs and reacts is what I feel change.

I think what you'd need is a plot of throttle body (or torque demand) vs throttle position. If you can get a rig set up for repeated throttle position (say always at 50%) and then you'b be able to show how that changes in throttle body or torque demand.

As for why its in the steering module, I'm sure VW has done crazier things in coding and modules.
 

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Discussion Starter · #6 ·
This

What you're logging would just be good for pedal box as the pedal box changes the input per position, i don't think the coding changes the input it changes the output.

Remember the throttle is just an input into the system the output is torque/accelerations. How the ECU interprets the inputs and reacts is what I feel change.

I think what you'd need is a plot of throttle body (or torque demand) vs throttle position. If you can get a rig set up for repeated throttle position (say always at 50%) and then you'b be able to show how that changes in throttle body or torque demand.

As for why its in the steering module, I'm sure VW has done crazier things in coding and modules.
But then why is it called "driving profile switchover" and then when you view that live channel "driving profile selection" you can see the impact of changing that setting - "incremental" causes the requested and actual values to change one after the other and "direct" caused them to change at the same time when you switch between modes that impact the steering (normal to sport or back again)? What has been described to me is that this changes the ratio like a pedal box - now your'e saying it's like a tune?
 
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I dunno, to keep the pesky kids from meddling with it. Sometimes you just gotta go with something and stop asking questions.
 

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I think what you'd need is a plot of throttle body (or torque demand) vs throttle position.
Did you mean pedal position? Cuz that's exactly what Karst logged and plotted in the first post. Throttle body and throttle position would be the same thing, no?

So what I am hearing is that some people suspect this affects the pedal vs throttle rate-of-change. That would be harder to log.
 

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Discussion Starter · #9 ·
I dunno, to keep the pesky kids from meddling with it. Sometimes you just gotta go with something and stop asking questions.
You mean having faith? Science. hahahahahaah

Good convo with you as always. Hope everyone on this thread is staying safe.
 
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Did you mean pedal position? Cuz that's exactly what Karst logged and plotted in the first post. Throttle body and throttle position would be the same thing, no?

So what I am hearing is that some people suspect this affects the pedal vs throttle rate-of-change. That would be harder to log.
Drive by wire has been around since what mk5, did mk 4 have them? There's no linkage between throttle pedal and the actual throttle body or fueling or wastegate/DV. AFAIK that the pedal is just a pot, and the ECU reads it and issues commands all the other systems to react and deliver a certain torqure/hp.

I have torque pro, not sure if the standard PIDs it can read what I think needs to be logged to show a difference.
 

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You mean having faith? Science. hahahahahaah

Good convo with you as always. Hope everyone on this thread is staying safe.
my tea leaves said i was going to have a good day today, so far so go! :D
 

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Drive by wire has been around since what mk5, did mk 4 have them? There's no linkage between throttle pedal and the actual throttle body or fueling or wastegate/DV. AFAIK that the pedal is just a pot, and the ECU reads it and issues commands all the other systems to react and deliver a certain torqure/hp.

I have torque pro, not sure if the standard PIDs it can read what I think needs to be logged to show a difference.
Yeah mk4 was also drive by wire. I guess what you might need to log is pedal position vs throttle position during transients, to see if there is delayed throttle response on the stock setting, vs "direct". The trick would be applying a calibrated pedal input, repeatably. But you could start with a simple pedal stab. Does the "direct" setting get the throttle open more quickly, or not?
 

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The positions that you are measuring are voltages off a potentiometer. I can't see how a computer tweak can change those voltages on the pedal, it can only change how the ECU interprets those voltages... which in turn would move the throttle flap differently, but the car might have to be running for you to log that change. Can you log it while running?

This is a great test, and I know you're on a personal jihad to prove the throttle tweak a placebo - but I did feel it on our two VWs, and it wasn't subtle. My wife couldn't tell any difference.
 

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Discussion Starter · #14 · (Edited)
The positions that you are measuring are voltages off a potentiometer. I can't see how a computer tweak can change those voltages on the pedal, it can only change how the ECU interprets those voltages... which in turn would move the throttle flap differently, but the car might have to be running for you to log that change. Can you log it while running?

This is a great test, and I know you're on a personal jihad to prove the throttle tweak a placebo - but I did feel it on our two VWs, and it wasn't subtle. My wife couldn't tell any difference.
Maybe folks aren't understanding what I logged - accelerator (as you said, this shouldn't change, it's a physical switch) to throttle (should be what changes as it is moving based on a drive by wire/formula/whatever) - if this change is doing what folks say, the second graph should have looked different as the throttle "flap" would have moved more per each movement unit of the pedal.
 

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Yeah but you also didn't measure what the ECU outputs.

Think of it as this, you peg the throttle right to the floor, (you've proven the ECU reads that it's pegged), Bbt its slippery out, there's tons of snow, ABS detected slippage and sliding sideways, it activates some calipers, ECU starts pulling power closes the throttle body.

You'd see a giant deviation from input (pedal position) to output (ECU fueling/power demand).
 

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if this change is doing what folks say, the second graph should have looked different as the throttle "flap" would have moved more per each movement unit of the pedal.
Only if the static calibration of pedal vs. throttle was changed. If the stock setting is merely a time constant, delay, or smoothing on the pedal inputs, it would only show a difference vs the "direct" setting during transient events. Does that make sense? In your logs, how fast did you apply increasing pedal?
 

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Yeah but you also didn't measure what the ECU outputs.

Think of it as this, you peg the throttle right to the floor, (you've proven the ECU reads that it's pegged), Bbt its slippery out, there's tons of snow, ABS detected slippage and sliding sideways, it activates some calipers, ECU starts pulling power closes the throttle body.

You'd see a giant deviation from input (pedal position) to output (ECU fueling/power demand).
The real throttle position is what the ECU commands (unless you have a throttle issue, it does what the ECU tells it to do). So he did log the real ECU output there. But you are right, there are tons of scenarios in which the ECU can decide to alter it's throttle position irrespective of pedal input. Any number of fault codes, traction control / vehicle stability. Many manufacturers even vary pedal inputs with ambient and engine temp for cold start protections, etc.
 

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But he also isn't displaying any delay between pedal position to reaction time. His graph is pedal vs throttle position.

Should be two lines, pedal position and throttle body position compared over time.

I don't think any one is questioning that if you put the pedal at say 50% the throttle body will react to 50%, but it's the time delay on how it reacts, direct being linear, stock is induced delay or "smoothing"
 

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But he also isn't displaying any delay between pedal position to reaction time. His graph is pedal vs throttle position.

Should be two lines, pedal position and throttle body position compared over time.

I don't think any one is questioning that if you put the pedal at say 50% the throttle body will react to 50%, but it's the time delay on how it reacts, direct being linear, stock is induced delay or "smoothing"
Exactly. This is the question. I would love to hook up my VCDS and try to capture said data, if my wife didn't keep sticking me with kid watching duties. :p
 

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my laptop has zero battery life (such as a vintage 2001 XP POS HP shop laptop should) so if I want to go for a drive I and log I gotta finally use that inverter way out back.

my only hope is torque app can read the proper PIDs to log.
 
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