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MY17 Touareg Wolfsburg
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Discussion Starter · #1 ·
Starting a new thread here to gauge what interest there would be to have the ability to change and control the torque convertor lock up for the Australian region T3 Touareg.

The Touareg is no doubt a great all rounder as a family car, perfect for the holidays, towing, and the long distant drives are comfortable but what I’ve found during city driving (which in my scenario is 90% of the time) the TC lockup logic really ruins the driving experience. Some other members have noticed this characteristic and have questioned it but for those that haven’t please let me know if this applies to you and if you would like to change something about it, understanding most have probably learnt to live with it or isn’t enough of an issue to bother them or just have not felt what the car could drive like if there was a change to the TC lock up logic.

Most should be familiar that once the transmission shifts into 3rd gear, almost immediately the TC lockup solenoid modulates and lock up occurs very early at approximately 30-32kms. It almost feels as if there was another gear change between 3rd and 4th gear. You may notice once the TC has locked in 3rd gear the engine RPM decreases and its at this point if you need to accelerate a little more the engine is now laggy and feels as if there is not enough power to get up and go, but there should be. You have your right foot planted and you are waiting a few seconds for the engine RPM to increase and build boost before the engine rpm reaches its peak torque band before it really gets moving. My observations is once the TC has locked in 3rd gear the TCM is very reluctant to unlock the TC whilst you are in that gear.

I also find in 3rd if you are off and on the throttle during slow speed driving, freeway traffic or whilst taking turns in motion or driving through a round about the acceleration tends to be a little jerky and hesitant and is due to the TC locking and unlocking 3rd gear and it’s mostly keeping the engine out of its torque band when you need it. This gear happens to be used a lot during low to moderate acceleration during the 20-50km speed range.

Trying to overcome and work though this inherent characteristic, I started off performing the throttle reset procedure, changed to the Cayenne transmission coding on VCDS, installed an EVC throttle controller and going through various settings to find one which wasn’t too sensitive but a setting which could decrease some of the throttle lag and then lastly a few months ago I had an engine remapped by Revo which I was hoping to correct some of the down low throttle performance and lag issues I’ve had with the car. None of the above has fully addressed the lag issue. They have all been small improvements with the engine remap adding a whole lot more of mid to upper range torque and power, I should mention that my engine is the 180TDi.

Not wanting to give up yet and what I feel is the only real short coming I had been searching for anyone that can tune and remap the TR80SD AL1000 TCM which I’ve found quickly that there’s very limited support and at this stage the only company I can find in Australia that can tune the AL1000 TCM with the map packs that are available can alter Torque curves, Torque clutch limit, Shift times, Shift tables and Shifting limits however the TC lock up logic is not one of them, at least for now and unsure if it will become available considering the Touaregs, Q7 and Cayenne are more of a niche market.

I decided to do some logs with VCDS to see what was happening with the TC lockup status and wanted to prove to myself that having the ability to change or delay the TC lockup would address the driveability issues I’ve found and more so with the throttle lag and performance down low.

So I had disconnected the N443 TC lockup solenoid wiring temporarily so the TC could no longer lock up, I can say since doing this and having the ability for the torque converter to stall during 3rd gear finally addressed the dreaded throttle lag as when needing to accelerate the torque converter can and will shoot to 2900-3000rpm (instead of being locked at the lower end of 2000rpm and below the peak torque window) this now has the rpm sitting within the engines peak torque curve window and the car actually accelerates and pulls effortlessly instead of the dreaded lag and lugging waiting for the rpm and boost to build which is a characteristic with a locked torque converter in 3rd gear.

I started searching for torque converter lock up controllers and interfaces to see what else is out there and came across a few company’s in Australia who create lock up controller kits but all of these company’s have there audience heavily targeted towards the Toyota 200 series Land cruisers, Prado, Hilux, Mitsubishi Pajero, Triton and Challengers and Patrols with nothing remotely close to supporting the Touareg, also the fact the Touareg is quite the opposite since the lockup occurs far earlier compared to the other cars which struggled to hold TC lock up, or don’t lock up till freeway speeds which needed a solution to lock the TC at an earlier speed to prevent excessive TC slip, heat, improve fuel consumption and engine braking whilst towing.

I was hoping for an easy solution such as a speed activated relay that would not allow the TC lockup signal to pass until a certain speed, but that has it’s short comings and I started to think if it were possible to delay the TC from locking up until a particular gear was selected such as 4th gear instead of 3rd. Now things start getting a bit more complex to control.

One of the vendors that makes TC lockup kits is MM4x4 vehicle electronics (MM4x4 | Torque Converter Lockup Kit | Adelaide | auto-mate|lockup-mate) he has some of the most advanced type of torque converter lock up controllers that reads data through the CANBUS and the controller is programmed specifically for that vehicle for when to apply and disengage the TC lock up. It uses a PWM signal to the TC solenoid the same as OEM’s do and allows the ramping of the TC solenoid for a smooth engagement as done originally. Having the ability to read info from the ECM / TCM though the canbus has a huge advantage as it brings the possibility of delaying the TC from locking up until a certain gear is selected. So I’ve reached out to Marshall from MM4x4 today and explained the situation here with the Touareg and if there is anything he can do in terms of making a controller that could delay and intercept the TC from locking up so early in 3rd gear and for example allow the factory TCM to pass its signal from 4th gear onwards only, and what other benefits it could potentially bring.

So here I am bringing this to your attention and to see if the current TC lock up logic bothers you at all, if you have noticed it would you like to address this if you could or is there anything else you would like to see? Ultimately if there is enough interest then it’s likely a project worth MM4x4 pursuing and in my opinion having the ability to delay the TC locking up so early and pushing that out to 4th gear improves the lag and acceleration immensely, too big to ignore.
 

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Really interesting post, Improve.

I've noticed what I think is the effect you are alluding to.

Cruising (and mainly in a deceleration mode) at lower speeds (25kmph - 40kmph), I notice that the motor/revs "floats" ... that is to say throttle response is negotiable/non-existent. I experience this when decelerating/cruising to a red-light, revs dropping, but still moving ... light turns green, foot gently on the pedal but BIG flat spot until the thing spins up again. I'll be more diligent now on getting better stats around whats happening when this 'effect' occurs.

I personally don't think it's as big a problem as the initial turbo lag (for the type of driving I do anyway). I have been doing some very minor snooping around to see if there is a fix for that ... wonder if a more responsive turbo would assist both issues? I am sure you would have a better idea than me, if it would. Thoughts ?
 

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Really interesting post, Improve.

I've noticed what I think is the effect you are alluding to.

Cruising (and mainly in a deceleration mode) at lower speeds (25kmph - 40kmph), I notice that the motor/revs "floats" ... that is to say throttle response is negotiable/non-existent. I experience this when decelerating/cruising to a red-light, revs dropping, but still moving ... light turns green, foot gently on the pedal but BIG flat spot until the thing spins up again. I'll be more diligent now on getting better stats around whats happening when this 'effect' occurs.

I personally don't think it's as big a problem as the initial turbo lag (for the type of driving I do anyway). I have been doing some very minor snooping around to see if there is a fix for that ... wonder if a more responsive turbo would assist both issues? I am sure you would have a better idea than me, if it would. Thoughts ?
@ smclaren. I think what you're experiencing is the transmission 'disconnecting' via the TC as you slow down, this is a design feature which the VW engineers think we need! Problem is as you have rightly pointed out that if or when the traffic ahead moves off and you also apply the throttle there is a lag that is most likely there to protect the transmission and TC from a sudden change in throttle position whilst the engine is 'disconnected' from the transmission!


As for the OP's original post I also have a dislike for the TC control tuning, there is certainly a sudden drop in RPM and torque as the TC locks up in 3rd gear and even with the V8 it is still very noticeable and at times quite annoying and somewhat disappointing. Its not difficult to avoid however as I have found the 'sweet spot' in the amount of throttle required to avoid this sudden drop in torque output however this is not always practical due to traffic conditions etc. Sport mode also helps reduce the effect as the transmission will hold the lower gears a bit longer so by the time the TC locks up in 3rd the car speed is higher and the torque drop is not as noticeable. When I'm towing the caravan I tend to use sport mode through towns and and when accelerating back to highway speeds I nudge the shifter over to manual mode and use the paddles, this effectively solves the problem when towing but its not really a viable solution during normal driving around town.

For the record I have a customer with a Cayenne Diesel S and his car does exactly the same thing as the Rline V8, so whilst the transmission tuning is noticeably different in the Cayenne the TC activity is the same.

Good luck with the search and yes you can count me in as a potential 'investor' in a tuning fix...
 

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Discussion Starter · #4 ·
I'll be more diligent now on getting better stats around whats happening when this 'effect' occurs.
That would be great, interested in everyone's feedback including what kind of driving you predominantly do city vs highway, if you have any issues with off road driving, towing, engine braking ect and perhaps list if you have the 150TDi V6, 180TDi or the V8 engine.

I personally don't think it's as big a problem as the initial turbo lag (for the type of driving I do anyway). I have been doing some very minor snooping around to see if there is a fix for that ... wonder if a more responsive turbo would assist both issues? I am sure you would have a better idea than me, if it would. Thoughts ?
If you have access to VCDS or a scanner, you may want to disconnect the TC lockup clutch solenoid wires like I did by removing pins 5 & 6 on the 8 pin transmission connector just for a short test drive to get a bit of a feel of how the transmission and engine responds during acceleration when it isn't forced to lock up so early and how much smoother it feels during those gears when coming off and on the throttle, I think it will surprise you. The 180kw CRCA engine has the GTB2260VK turbo with peak engine torque from ~ 2500rpm vs the 150Kw CJMA engine having the smaller GTB2056 turbo with peak torque from 1950rpm, I would expect on the 150kw engine models with no air suspension that with the TC locking so early it wouldn't be as unresponsive as the 180kw Touaregs. The engines with the smaller turbo make less power and torque overall than the 180kw both in original form and once remapped. The trade off with the 180kw engine is certainly 500rpm or so of more lag comparing like for like. In saying that I expect there to be the lag when coming off and on the throttle with the TC locking and unlocking like it does.
 

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Discussion Starter · #5 ·
As for the OP's original post I also have a dislike for the TC control tuning, there is certainly a sudden drop in RPM and torque as the TC locks up in 3rd gear and even with the V8 it is still very noticeable and at times quite annoying and somewhat disappointing. Its not difficult to avoid however as I have found the 'sweet spot' in the amount of throttle required to avoid this sudden drop in torque output however this is not always practical due to traffic conditions etc. Sport mode also helps reduce the effect as the transmission will hold the lower gears a bit longer so by the time the TC locks up in 3rd the car speed is higher and the torque drop is not as noticeable. When I'm towing the caravan I tend to use sport mode through towns and and when accelerating back to highway speeds I nudge the shifter over to manual mode and use the paddles, this effectively solves the problem when towing but its not really a viable solution during normal driving around town.
Interesting to hear that you feel this in the V8 with the amount of torque that engine makes. Lets hope we can get to the bottom of it and find a solution. It could end up being replicated to the Cayenne's and Q7's too if the TC lock up logic behaves in the same manner.
 

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Interesting to hear that you feel this in the V8 with the amount of torque that engine makes. Lets hope we can get to the bottom of it and find a solution. It could end up being replicated to the Cayenne's and Q7's too if the TC lock up logic behaves in the same manner.
One of the problems is the electronic throttle control, I'm 100% sure that the ECU is pulling the throttle back at the same time so the extra torque from the V8 doesn't really come into play.
 

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@improve - really great post and tons of clear info - good job and well done explaining.

I'm not sure if he can alter the lockup point / characteristics but try giving DTA at Mascot a call and speak to John. He has the knowledge and ability to remap the transmission so might already have a potential fix for you with regard to programming.

Oz
 

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Discussion Starter · #10 · (Edited)
I have the same issues with TC,
I'm basically trying to force the cluth to slip more on 1st gear, so i can simulate a low gear for low offroad
I can grab a photo of the connector tomorrow however it is on the RHS of the transmission. You can access this without having to remove any covers.
The wires you are looking for are sitting in pins #5 and #6 of the 8 pin connector, colours blue/black and red/green. Just need to remove one of those pins and tape it up temporarily whilst you perform a test.

Adding a manual bypass switch to simply divert the TC signal to a resistor to trick the TCM so it recognises a load and doesn't fault might be possible, but that's not what I'm after for several reason however it may suit your particular scenario that you mentioned.
Bare in mind if leaving the TC solenoid bypassed for too long eventually the TCM will recognise that the TC is not locked due to the engine rpm and TC rpm difference.

I would like hand over from the TC solenoid bypass back to the TCM controlling fully automated also as the TCM sends a ramped PWM signal during lockup to ensure a smooth engagement if you happen to just flick your switch when the TCM has already commanded full lockup its likely you will have a bit of a thump/harsher engagement. That's part of the reason for having the handover during a gear shift.

Also the logs I have done so far with the type of driving I do shows that my TC does not lock up in 1st gear or 2nd, the status in vcds remains 'open'. Only 3rd gear onwards the TC locked.
This may not benifit you at all if 1st gear is your concern.

Cheers
 

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I have the same issues with TC,
I'm basically trying to force the clutch to slip more on 1st gear, so i can simulate a low gear for low offroad
I think you'll struggle with that plan. The TC slip is governed by its internal design, its not controlled by a computer, they have a designed stall speed which in the case of the Diesel Touareg is quite low at around 1,000 rpm. The Torque Converter (TC) is also quite 'low tech' all it does is transfer torque based on its internal design, its not actually controlled by the transmission computer and as such can't be 'reprogrammed' The TC lockup clutch is activated by oil pressure, the transmission computer controls the lockup function by diverting oil through the input shaft to the TC clutch at a pre determined time so in some ways this could be altered via software tuning however the TC lockup clutch will either engage or disengage, its not designed to 'slip'
 

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Discussion Starter · #14 · (Edited)
Hi All, long post. It's been a few months since I've added to this but I can happily say I have a solution and made a controller for delaying the torque converter lock up, and what a difference it makes. No joke.
I know this thread didn't get as much attention as I thought it originally would have, which I found surprising though I think most don't know any different and are so use to engine and transmission performance how it is. For me this was an absolute deal breaker, because as previously mentioned I tried the throttle controller, cayenne trans coding, had the engine remapped but nothing corrected the reduced torque and lag around 3rd gear which really does affect how the car drives in general.
I also looked into having the TCM remapped however altering the torque converter lock up points wasn't possible. Everything else about the car is great just the TCM tune is 100% more orientated for keeping emission's low by keeping the engine out of its peak torque window as much as possible by default, and by having the TC lock so early in 3rd gear and at such a low speed ~30-32km's it does that just perfectly, BUT at the sacrifice of reduced torque, less acceleration performance and less acceleration response.

The controller completely eliminates the reduced torque and lag specifically in 3rd gear so now when accelerating in D3, the engine rpm can flare up so its sitting in its peak torque window immediately and the acceleration and boost is instant, and how it should be imho. D3 gear is used a lot during local / city / low speed driving or when slowing to approaching roundabouts / exiting roundabouts you are in D3 or when entering and and then going to re accelerate as you are exiting corners you would be in D3, or just accelerating or to over take these are the times you really notice the difference. Having the ability to accelerate effortlessly makes a world of difference on how the car drives and feels. The engine always had the power there, just it was being held back.

Previously when the TC would lock, the engine rpm is reduced down to around 1700rpm in D3. This is where the lag starts from, so when needing to accelerate from this point the engine is sitting well outside of its peak torque window. The result is having no where near as much torque that could be available so the engine lug's and lags until the rpm rise's to where boost is made, which on the CRCA engine peak torque isn't until 2500rpm.
The controller also smooths out some of the vibrations/clunk/jerky feels whilst in 3rd gear that is naturally there when the converter would have normally been locked, you would feel this when coming off and on the throttle in 3rd gear as the converter unlocks and locks, I first observed and confirmed this with VCDS when monitoring the torque converter status.

So how I did it.
First I reached out to all of the vendors that currently make torque converter controller to see if its something they wanted to tackle however most didn't want to look into it since the Touareg market is small, or they had other priority's so this wasn't going to move along as quickly as I would like. Also all of the current vendors make torque converter lock up controllers, not UN-lock up controllers which is what the Touareg actually needed. I knew how I wanted to controller to operate the "delaying and handing back over to the TCM" piece, but I needed information from the transmission canbus to achieve this, so I started researching everything I could about canbus systems and canbus hacking.

Once I had my head around that I built a canbus sniffer, so I could start collecting the raw canbus traffic and messages that are being communicated on the powertrain bus. I quickly realised how busy the canbus is on the Touareg even with just the ignition on, so trying to filter and locate the ID relating to the transmission and canbus message and byte specifically for the actual transmission gear selected wasn't going to be easy, but eventually I got there once I found some software that made reading the traffic a lot easier.
Once I nailed down the canbus ID, message and byte responsible for the "actual gear selected" that was one of the hardest part's done. So now with that data the controller is constantly listening to the canbus traffic and whenever D3 (and only D3) is selected, the controller see's that canbus message and then closes the contacts on two relays to divert the two wires that were going to the N443 lockup solenoid and now sends and completes the TC lockup circuit through a 50w load resistor to mimic a load on the circuit (this is required otherwise there would be an open circuit and subsequently P2757 would be flagged), as soon as the transmission shifts out of D3, the two relay's de-energise and contacts open again so the N443 solenoid circuit is handed back over and has continuity directly to the TCM as it normally would have. The only time the relays are energised is only when the transmission selects D3. Once the transmission shifts into D4 the torque converter locks up as it normally would have after a gear change has taken place, which is near on immediately. You hardly notice the torque converter locking up now since the gear ratio in 4th gear is more closely matched to the engine speed so it's very seamless comparing to the original TC locking up in 3rd gear it is very noticeable by the large reduction in engine rpm as is slips and modulates until the converter is locked.

Completing my validation testing, I was surprised that the TCM/ ECM didn't recognise that the TC was not locked in 3rd gear when it would have normally been commanding it (and that would have been my next hurdle to overcome if it did happen), since most TCM's are comparing the transmission input shaft speed to the engine speed to determine if there is an issue with the TC solenoid or TC operation since a locked TC speeds would be very similar to engine speed. I couldn't find any information specific to the Touareg on the logic or threshold before flagging a P2757, but I did find some info on the Toyota Aisin 6 speed transmissions, my only theory is the the TCM is not looking for a close match at such a low gear and speed, and is likely only looking for that in taller gears and when you would likely be travelling at greater speeds.

The controller is mounted neatly under the drivers seat, since this is where the TCM is located. I had to tap into the can high/can low wires, and cut the two N443 solenoid wires near the TCM connector. The controller is powered via a USB cable currently which makes turning off the controller easy so the TCM can function completely original if needing to. I will look at hard wiring the power supply soon and mounting a switch in the centre console.


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Discussion Starter · #16 · (Edited)
Nice work. Luckily my V8 does not suffer this issue :)

cheers
Rohan
I suspect it wouldn't feel remotely the same since the torque starts flat lining and peaking at around 1800 rpm on the V8, you are placed very close and within the peak torque window even when the converter does lock up in 3rd gear 😁

Although the ability to have a loose converter in 3rd gear even with the V8 would have benifits with acceleration whilst in D3 too.

I have not come across any cars yet that lock the TC in 3rd gear and at such low speeds. Almost all are closer to highway speeds or at least above 70km's.
 

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@improve - that is some seriously cool engineering, especially how you were able to discern which information you needed to grab out of the ocean of data.

If nobody else chimes in and says it, I will, excellent work!!

Coming from the Ford world, especially American Fords, there is an engineering genius available to create any part needed to make em faster, stronger, more reliable, and especially fasterer. It's a different world in VW land but to see what you have achieved is truly good work.

In my earlier post when you first raised this topic, I suggested giving DTA at Mascot a call. I think John would be very interested in your little black box and you might be able to do a commercial deal with him. Worth a shot...

Oz
 

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This is some amazing work improve. I am blown away that you have the knowledge and skill to digest that and bypass it. I sure wish I could ride in your Touareg to feel the difference. I would probably be asking for one myself. Congrats on the accomplishment. I don’t like the RPM drop in 3rd either so this could be beneficial to other people. Maybe you should strike a production deal.
 

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Discussion Starter · #19 ·
@improve - that is some seriously cool engineering, especially how you were able to discern which information you needed to grab out of the ocean of data.

If nobody else chimes in and says it, I will, excellent work!!

Coming from the Ford world, especially American Fords, there is an engineering genius available to create any part needed to make em faster, stronger, more reliable, and especially fasterer. It's a different world in VW land but to see what you have achieved is truly good work.

In my earlier post when you first raised this topic, I suggested giving DTA at Mascot a call. I think John would be very interested in your little black box and you might be able to do a commercial deal with him. Worth a shot...

Oz
Thanks Oz! it certainly feels like an accomplishment. It's a hard bunch here to get any feedback or input on the the topic with 1000 views and only a couple of posts.
I did follow your suggestion originally when I was seeking those in Australia that had the ability to tune the AL1000 TCM to see if they could make changes to the TC lockup logic, I tried reaching out to DTA and speak to John, but he must be a busy man! On two different occasion's when I was greeted from the admin/reception, they took my enquiry and my details but I never heard a peep back.
 

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Discussion Starter · #20 ·
This is some amazing work improve. I am blown away that you have the knowledge and skill to digest that and bypass it. I sure wish I could ride in your Touareg to feel the difference. I would probably be asking for one myself. Congrats on the accomplishment. I don’t like the RPM drop in 3rd either so this could be beneficial to other people. Maybe you should strike a production deal.
Thanks Brobb :D, I can't see why I couldn't ever ship one to you.

The best thing I can do at the moment is let any of our fellow Perth Touareg owners see what it's like in my car to build some third party feedback, the difference really is night and day.
 
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