VCDS Torsion Value

dj_efk said:
Yes I know - this figure is abnormally good from literally almost everyone else with an ATL. You have previously stated you don’t drive slowly, just keep to the speed limits when cruising, which I do as well:

In Akoya, I can just about get to 63mpg over a tank if it has been all long journeys and I try really hard for all of that time.

In Audrey, I can’t get quite as good figures, despite their specs being identical (apart from Audrey having the @timmus intercooler and a PTW instead of a MYP, both of which combined should, if anything, help rather than hinder consumption figures. Both cars have working thermostats and temp sensors, both cars are freshly serviced, both cars are on the same wheels (pepperpots) and high efficiency tyres set to full load pressures per the sticker.

Now I don’t doubt you’re a pro hypermiler and incorporate many fuel-saving techniques into your driving style, yet the fact remains you are consistently able to get at least 10% better figures than the rest of us who watch such things (therefore it is reasonable to assume that “us” drive more economically than most). This plus the fact that I get different results from two near-identically spec’d cars leads me to conclude there may be something else mechanical in it that can vary from one car to another. I think this TV setting could account for some of that. @Edwrai - have you ever checked what TV your engine is set to run at? Could you check next time you have VCDS hooked up?

I will be fitting Audrey with one a @depronman EGR housing next time I have my cambelt done, as I do believe that will help also.
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I also run pepperpots with cross climate tyres. Also worth noting I use a 195 55 15 tyres which is the same outer diameter as the standard setup on an a2. If you are running larger diameter tyres this would reduce your indicated speed and your mpg.


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Howey said:
Edwrai

Have you ever checked your torsion value in vcds?

Regards

Howey
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I haven’t but it’s been apart and back together being set at the correct values twice, doubt it’s off.


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A few snap shots
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And a few at around 2000 rpm
 

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To be honest i am suprised how much the torsion value alters even at idle what they show i dont really know.
However car seems to pick up better at lower revs (maybe i am kidding myself)
Figures show reduced fuel consumption at 2000 rpm.
Maybe me but i could swear it hardly smells now (exhaust gases)
Only time will tell!!

Cheers

Howey
 
Howey said:
Mini update

Tried adjusting the cam by turning 18mm head clockwise this seemed to make the reading go more retarded -2.2, so turned anti clockwise (just as DuncanA2 had said), moved a fair bit and this seems to now be reading 2.2 which i take it as advanced, coolant temp was below 80 around 65 so i need to confirm readings when proper engine coolant temp is reached but although 0.0 to 0.5 to 1.0 is the optimum i am hoping to try around 2.0 as already mentioned 2.2 is a sweet spot for some!

Daughter has Brownies so all a mad dash lol!!
Click to expand...
In terms you have advanced and retarded backwards. Negative figures means advanced and positive figures means retarded as I corrected earlier.
As @RAB states, you have believers and non-believers. I won’t argue with that. To me the interesting part is that you will actually move the torque band up and down the RPM range as you make adjustments.
Your idle compensation will alter as you make adjustments, as well as your idle consumption. That is a fact. The main reason for the provision to fine tune is that the lockingtools do not absolutely lock the camshaft and crankshaft, there is some play of up to 2 degrees.
I hope @Howey can confirm that symptoms that advancing the TV will ease engine (cold) starts and provide torque higher in the RPM range at a cost of economy. The opposite (more retarded) positive TV will provide more torque down the RPM range and will decrease earlier in the higher RPM. Possibly more troublesome engine starts. Hence the consensus would be to zero the TV out. If a cambelt change has been performed correctly than the bolts that hold the CS sprocket will be in the middle of the oval-shaped holes which make the adjustments possible. It all depends on what you are aiming for. The gain always has a cost in this case . I’ve run a long time on TV of around +2.2. Good torque down low with good economy whilst driving moderate, 68mpg. But when I step on the pedal I lost some power which I gained by adjusting to TV 0.0- +0.6. This gave me more torque higher in the RPM range (>3000rpm) at the expense of some economy, now 62mpg. This is with rather bad injectors, so there is still some room for improvement.

Im not trying to convince anybody, but just sharing my thoughts and experiences.
 
The ideal idle consumption for our 1.4tdi 3-pots is 0.4 L/h and around 2.4 L/u at 2000rpm stationary I believe. I cannot reach the latter but at idle I’m as close as you @Howey ??.
My tip is to adjust TV what you feel is right and drive the car as you would normally do for a week or so. This way you have a fairly good comparison to what you were used to under those circumstances. Then if need be you can adjust again in accordance to your goals. In addition to what has been mentioned before, clockwise adjustment is more in direction of how the engine turns over, so in fact advancing the camshaft. Counterclockwise you will retard the camshafts position. More retarded gives a more smooth idle as a bonus in my experience as opposed to more advanced TV .

Happy adjusting ??
 
@DuncanA2 - Thank you for such concise and informative posts - these are just what I have been looking for now for a long time.

Can you or anyone else give a step-by-step on how to actually make the adjustments, starting with whether the cambelt cover needs to be removed in its entirety or else can you flex it out of the way after removing the more accesible bolts? And how does one ensure you don't adjust it to much one way or the other, as I understand the needed range of adjustment to be so small it would be imperceptible, surely?
 
Hi,

There has been a lot written on the internet about this subject. According to VCDS there is a -3 to +3 degrees window to allow the adjustments. But in reality you can adjusting in a greater range than this, so make very small adjustments. If your cambelt is replaced the right way, than there is very little risk you will cause any damage. Usually the TV will fluctuate a bit, even at idle. This is ok . If the TV stays at 0.0 at all conditions than you made the adjustment out of range. The car would still run, but not as it supposed to be. Just simple re-adjust in the opposite direction a bit until you are within range again. I’ve had the TV at -6 degrees , so the TV allows for more range than is given by VCDS.
That said, here’s a link to what I found to be very informative and helpful.

www.myturbodiesel.com

PD Engine Torsion Value - Solid Information About Why...

www.myturbodiesel.com www.myturbodiesel.com

PD Engines - The Problem of Setting Torsion Value

Since first working on the PD motors, we found the setting of the torsion value a bit of a mystery. The torsion value is located in VCDS/Engine Module/ block 4/ torsion value. We tended to figure that 0.0 was a good figure and originally let it go at that. However, early on, we had a Passat...
forums.tdiclub.com forums.tdiclub.com

community.dieselschrauber.org

Steuerzeiten & PD-Elemente einstellen Pumpe Düse Motor (Fachartikel)

Die Nockenwelle des 1.9l/2.0l 8V TDI PD-Motors bewegt nicht nur die Ein- und Auslassventile, sondern (über Rollenkipphebel) auch die PD-Elemente (PDE). ...
community.dieselschrauber.org

The last one provides a step by step, but is in German . May be a problem for some.

Hope this helps and I too enjoy this topic. Here in the Netherlands there are very few as well that can be bothered with this issue. Mainly due to not knowing what you don’t know. And because most do not experience the subtle differences. If you drive a lot of miles / kilometers in your ATL, AMF or BHC you probably know your engine like the back of your hand and I think you will appreciate the improvements ?
 
I simply removed bonnet, engine top cover, unhooked timing belt top cover pull it up a bit and then back towards the mounting, my first thought was damm the wipers in the way so need to lower engine however simply gently trying to move cover and sort of twisting in a clockwise direction worked!

Use a fine felt pen to mark the camshaft to sprocket hub and you know where you started if things get confusing. I found must over stuff online to be confusing but the DuncanA2's advice was just what i needed!! Many thanks Duncan!!
 
DuncanA2 said:
In terms you have advanced and retarded backwards. Negative figures means advanced and positive figures means retarded as I corrected earlier.
As @RAB states, you have believers and non-believers. I won’t argue with that. To me the interesting part is that you will actually move the torque band up and down the RPM range as you make adjustments.
Your idle compensation will alter as you make adjustments, as well as your idle consumption. That is a fact. The main reason for the provision to fine tune is that the lockingtools do not absolutely lock the camshaft and crankshaft, there is some play of up to 2 degrees.
I hope @Howey can confirm that symptoms that advancing the TV will ease engine (cold) starts and provide torque higher in the RPM range at a cost of economy. The opposite (more retarded) positive TV will provide more torque down the RPM range and will decrease earlier in the higher RPM. Possibly more troublesome engine starts. Hence the consensus would be to zero the TV out. If a cambelt change has been performed correctly than the bolts that hold the CS sprocket will be in the middle of the oval-shaped holes which make the adjustments possible. It all depends on what you are aiming for. The gain always has a cost in this case . I’ve run a long time on TV of around +2.2. Good torque down low with good economy whilst driving moderate, 68mpg. But when I step on the pedal I lost some power which I gained by adjusting to TV 0.0- +0.6. This gave me more torque higher in the RPM range (>3000rpm) at the expense of some economy, now 62mpg. This is with rather bad injectors, so there is still some room for improvement.

Im not trying to convince anybody, but just sharing my thoughts and experiences.
Click to expand...
Just thinking Duncan (i know its dangerous)
Did you try any higher than 2.2?
 
Hi, I’ve seen TV of -6 degrees. But I wouldn’t advice that. More than + or - 3 degrees would suggest the cambelt is a tooth off its correct setting. But if you try it won’t harm to the extend that you will ruin your engine. ?
 
Ref this old post, last time I replaced the cambelt the torsion value was +4.8.

Today I.....

Visited the Angel of the North...
www.a2oc.net www.a2oc.net
As many previous threads have indicated, the process only really applies to old generation Audis with the Bosch VE fuel system. Striving for a 'Zero' reading (as I have also done) on the PT fuel system is no guarantee of optimised cam (valve and injector) timing. It does however facilitate trial and error tinkering and allow us to go back to the original 'timing tool' setting if necessary

Cheers Spike
 
DuncanA2 said:
The main reason for the provision to fine tune is that the lockingtools do not absolutely lock the camshaft and crankshaft, there is some play of up to 2 degrees.
Click to expand...
Really? Once fitted, the locking tools don't allow any movement, hence the name. In fact the only way to fit the crankshaft locking tool is to place it on the sprocket and turn the crankshaft while applying inward pressure to the locking tool.

RAB
 
Yeah thats it so 0.0 the "ideal"

What mpg under what conditions do you get?

What diagnostic software is that?
 
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