PD Torsion ??

So I recently changed the timing belt on my BEW Golf and got the belt to where the crank and cam locks would go right back into the slots after rotating the belt around twice. Then I checked the Torsion value in VCDS after getting the engine warmed up and it is +1.5. After reading through some threads on here, I see that there is a preference to have it at zero.

If I were to adjust the torsion down as some suggest, wouldn't that get the belt out of correct timing per the rotating-and-checking-with-the-locking-tools-method? Just curious as there seems to be a contradiction here. Thanks.

Bentley mentions nothing about checking the torsion value, so as long as the lock tools are used, you are close enough, per Bentley. But it appears that setting the the torsion value, using a VCDS, is a way to fine tune the valve timing (I think the ECU sets the injection timing if the camshaft is statically timed within a certain range). The lock tools set the static timing and the torsional value measures the real (dynamic) timing and will be more accurate.

I bet if you adjusted the torsional value to "0", the lock tools would still fit well. I think that is how fine the adjustment is.

After I relpaced my timing belt I measured torsional value and it was reading +2.5 deg. KW and I was extremely maticulous and had it where the lock pin slid in real easy into the camshaft hub (with the crank lock engaged). I left it at that value for about 20,000 miles.

Recently I adjusted the torsional value down and first try I got it to +1.5 degrees KW and I decided to leave it at that. The distance between the bolt heads and the ends of the slots on the camshaft sprocket were ever so slightly changed, so little so I had difficulty seeing any change. That is how small a change makes the torsional value change. I noticed that the idle stabilization values between injectors got a good bit closer (better) and I noticed about a 1 - 2 MPG increase in mileage (I keep very accurate mileage records and drive consistently).

I noticed no change in performance.

I have been at 1.5 deg. KW for about 5000 miles now and am contemplating on bring it to around +0.5 deg. KW. I'd be interested to see if mileage and idle stabilization gets even better.

I would like to know if there is additional information on the torsional value and what it means and where it should be set, other than what I read on here (although this is good info). I would like to know how "0" was picked as the best value. I have not seen that documented anywhere, other than mentioned here.

--Nate

Not to change the subject, but I just googled on "torsional degrees KW" and I get this:

http://pubget.com/paper/12544339



--Nate

I just adjusted my torsion value to 0.5 Degrees KW. The idle stabalization got a bit worse. Here are the idle stabalization and torsion values for the three settings over the last couple of years:

After timing belt replacement I had a torsion value of +2.5 deg. KW and an idle stabalization value range of +0.42 to -0.16 mg/stroke.

22,000 miles later I readjusted and got a torsion value of +1.5 deg. KW and the idle compensation smoothed to a range of +0.12 to -0.14. I noticed mileage improve by about 2 MPGs.

Today (about 3,000 miles later) I readjusted to a torsion value of +0.5 deg. KW and the idle stabalization range increased to the range of +0.35 to -0.33.

If fuel economy goes down I'll readjust back up to 1.5 deg. KW. I was surprised the idle stabalization got worse.

--Nate

Nate,
Check the stabilization values after a day or two of operation. I would be interested to see if they alter.
Dan

Will do Dan. The engine was warm, but may not have been at full operating temperature when I checked the adjustment. Car was at operating temperature when I began the adjustment, but its about 30 degrees F. and windy outside, so the engine cooled quickly while I was changing the setting. The temperature guage was a little below the fully warm indication of 190 deg., when I ran the VCDS, so maybe that has something to do with the values.

But with the change the engine idle seems quiter, smoother and actually a hair faster and with slightly less "diesel" sound.

--Nate

Thanks for the replies. I didn't check the Torsion number before I changed the timing belt but it seems to me that the engine vibrates slightly more at idle afterwards. Also, it occurred to me that the the cam and crank were not exactly in line before changing the timing belt. It was close. I had to wiggle the cam a bit to get the cam tool in when the crank was locked. So maybe there is some room for adjustment.

Okay, so I couldn't help myself and went to mess with the torsion. On my first try I went from 1.5 to 1.0 and I couldn't tell if I had actually moved anything. Then I tried again and it went to -1.0. Oops. I could see it move that time. Next try I got it up to 0.5, which is where I decided to leave it. I also checked the idle stabilization numbers at each step. Here they are:
(Torsion) Idle Stabilization
(1.5) -0.28 to 0.19
(1.0) -0.38 to 0.21
(-1.0) -0.28 to 0.26
(0.5) -0.26 to 0.24

So the overall range didn't change all that much but it was interesting in that the it shifted among injectors which deviated. So for torsion of 1.5 the injectors were -0.28, 0.19, 0.00, 0.02 and for the torsion of 0.5, the injectors were -0.26, 0.02, 0.00, 0.24.

I could definitely tell that lower torsion resulted in a smoother, quieter idle and smoother revving. It was like how the car was before I changed the timing belt so I am happy with it.

DanG144 said:

Nate,
Check the stabilization values after a day or two of operation. I would be interested to see if they alter.
Dan

Click to expand...

I just did last night. At idle, immediately following a 25 mile drive. They were MUCH better. The variance was only +.12 to -.14. The torsion value was still at 0.5 degrees.

--Nate

Negative Torsion Value

I'm a newbie. My vag-com shows -5.9KW for the torsion value with the engine temp at 84c. Isn't this extremely retarded?

hyperhyper said:

I'm a newbie. My vag-com shows -5.9KW for the torsion value with the engine temp at 84c. Isn't this extremely retarded?

Click to expand...

IIRC, the acceptable values are +3 to -3KW. It would appear that yours is out of range.

Yes. The suggested range is 0 to +1 degrees KW. Its fairly easy to change and after a time or two you can change it in 10 minutes.

For a BEW, unclip the rubber air hose to the throttle assembly and wiggle out the timing belt upper cover (there are two clips on it to undo). Loosen the three 13 mm bolts for the camshaft sprocket adjustment. Take an 18 MM wrench or socket and place it on the camshaft hub bolt (the big center bolt). REMEMBER a little goes a LONG way. Now bump the camshaft CLOCKWISE with the wrench/socket to advance the camshaft timing. You should note the position of the three 13 mm bolts in their slots in case you apply too much force and go way to far. You want them to move perhaps half a mm, possibly a mm at most, since you are off quite a bit. I changed mine from +2.5 and I bumped the cam and I barely saw the slot distance on the cam adjuster bolts change and I was then at +1.5.

Next tighten the three camshaft sprocket adjustment bolts (I think it is 25 NM/18-ft-lbs) and slip your air intake hose back into the throttle/EGR housing and check the adjustment. If off, repeat. When done, reinstall the upper timing belt cover. Remember counterclockwise retards the camshaft timing (makes the KW value more negative, the number lower).

--Nate

PD Torsion?

PDJetta said:

Yes. The suggested range is 0 to +1 degrees KW. Its fairly easy to change and after a time or two you can change it in 10 minutes.

For a BEW, unclip the rubber air hose to the throttle assembly and wiggle out the timing belt upper cover (there are two clips on it to undo). Loosen the three 13 mm bolts for the camshaft sprocket adjustment. Take an 18 MM wrench or socket and place it on the camshaft hub bolt (the big center bolt). REMEMBER a little goes a LONG way. Now bump the camshaft CLOCKWISE with the wrench/socket to advance the camshaft timing. You should note the position of the three 13 mm bolts in their slots in case you apply too much force and go way to far. You want them to move perhaps half a mm, possibly a mm at most, since you are off quite a bit. I changed mine from +2.5 and I bumped the cam and I barely saw the slot distance on the cam adjuster bolts change and I was then at +1.5.

Next tighten the three camshaft sprocket adjustment bolts (I think it is 25 NM/18-ft-lbs) and slip your air intake hose back into the throttle/EGR housing and check the adjustment. If off, repeat. When done, reinstall the upper timing belt cover. Remember counterclockwise retards the camshaft timing (makes the KW value more negative, the number lower).

--Nate

Click to expand...

Thanks PD.... I changed it today. Got it to 0 on first try. Thought seriously about leaving it there, but I wanted to advance it a bit more, I finally got it to 1.5 on about the 6th try. It sure runs a lot better now. Will be checking mileage, but assume an improvement there also. Appreciate all the help.

Torsion adjustment?

Hello folks, I know this thread is kind of old. But reading it, I have trouble finding this setting in my VCDS , I have the latest version I think it is 11.11
Does anybody have clear steps how to look the values in the new VCDS ?
Thanks