Completely mental torsion values. Stretched belt? Failing tensioner?

Hello TDI Club. This is my first post. I've been lurking for a while and have read a reasonable amount on "torsion". I gather it is quite a dark art.

I understand that a true reading of 0.0° is the aim. With fine tuning from there based on how your individual car runs best. I also gather that if you are way out of spec it will just show 0.0 without any fluctuation. I've seen a lot of 0.0 recently, but definitely the latter option rather than a true 0.0.

Here is a quick log from VCDS of my torsion earlier today:

Time Torsion
0.01 0.0
0.17 34.8
0.33 0.0
0.50 32.8
0.66 48.0
0.83 31.4
1.00 47.0
1.16 41.2
1.33 0.0
1.50 37.2
1.66 51.9
1.83 34.3
2.00 0.0
2.16 32.3
2.33 0.0
2.50 31.4
2.66 47.0
2.83 30.4
3.00 46.6
3.16 62.2
3.33 62.2
3.50 62.2
3.66 62.2
3.83 50.5
4.00 62.2

There was a -13.2 a little while after that. Clearly these numbers are physically impossible. The sensor is new so I can rule that out. I'm also fairly certain the wiring to the sensor is okay based on what I've seen on a volt meter but I'm not an expert.

Can a damaged belt/tensioner/idler/pump lead to these kinds of numbers? One minor tell is that my tensioner's little arrow doesn't stay in the same place. The arrow oscillates back and forth about the width of the cut out (or window) that it sits in front of. Is this normal behaviour?

The car has a strange hot starting problem (bad noises) which improves if I just unplug the camshaft position sensor so I do think I'm getting to the cause of the hot start problem with these numbers. I just don't know what is causing the numbers.

I'm grateful for any input.

I have read, if the torsion setting is too far out + or - it will default to 0 in Vagcom. O try to get mine at .5+

I ran my BEW PD at various different torsion settings as an experiment to see the difference. I had it as far as 9.+ (ran good but logged code) to -.5 (didn't like it at all especially idle roughness).


I eventually ended up at 6.+ and left it there. Ran good and strong, good idle smoothness, no CEL, good economy.


Sold the car and set it back to 4.0+ just to be safe. New owner has put 30K miles on it and loves it. He commutes 90 miles a day 4 days a week in it.



If I do a timing belt job I usually shoot for 1.0+ just to be believable if it goes to another shop to avoid criticism, but my personal favorite is 2.5+ overall on the BEW anyway. BRM seems to like that setting too.

To be clear about the values I'm seeing I've made a video. You can see the highly unstable values; https://www.youtube.com/watch?v=D-DPgszFntg.

This means I am unable to tune the torsion values. I cannot get stable values.

I have replaced both the camshaft position sensor and now also fitted a new timing belt kit. No improvement. Has anyone had this experience before?