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Discussion Starter #1
There's already an existing article on adjusting camshaft torsion after doing a timing belt on a SOHC PD engine here http://www.myturbodiesel.com/1000q/multi/PD-adjust-Idle-TDI.htm

but I added a video today:http://youtu.be/pAEmqvUpKEY

Basically, this is an optional but suggested step after replacing the timing belt on any VW TDI or Audi TDI pumpe duse engine (PD). A SOHC engine is shown, I'm not sure what extra steps a DOHC would require.

This could also fix a rough idle if the rough idle is caused by timing that is off or has retarded over the life of the timing belt. Another common cause of rough idle is a bad flywheel or bad camshaft. See the FAQ for more on these separate topics.

This will not adjust idle rpm speed since that is computer controlled. This only adjusts the camshaft timing. PD engines not only have to open the valves but they also pressurize the fuel injectors. The solenoid (or piezoelement on newer Euro market engines) then releases the fuel.
 

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Hi Chitty,

From what I've read - you adjust the front intake cam to get the torsion.
You then adjust the rear exhaust cam by the same as the front.

I had to adjust the front cam by about 4mm.
The problem is I only had 2mm of play on the rear cam before the bolts got to the end of the oval slots!
(the front cam bolts are in the middle of the oval holes)

I still have a slightly lumpy idle and my fuel consumption isn't great.

I'm wondering if I should try adjust the rear cam (to get the bolts in the middle if the slots) the other way mm by mm to see if that improves things.
Can this do harm if I make the adjustments in very small stages?

Any advice would be really appreciated!
 

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Ok - thanks anyway.
And thanks a lot for the write up on fine tuning the cam timing. Perfect detail and appears to have helped A LOT of people across the forums :)
 

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Does changing the torsion value affect the IQ? Does going from +1 to +1.5 increase the interval for time of the fuel to be injected? As you can tell I'm not terribly clear what exactly increasing or decreasing the timing does (i.e. BTDC or ATDC) does with regard to the injection of fuel.
 

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Does changing the torsion value affect the IQ? Does going from +1 to +1.5 increase the interval for time of the fuel to be injected? As you can tell I'm not terribly clear what exactly increasing or decreasing the timing does (i.e. BTDC or ATDC) does with regard to the injection of fuel.
The inj. open via solenoid and I'm not sure how changing timing would change that, that's all done in ECU. But there's an optimal range for cam because the cam is actuating the plunger to pressurize the fuel which is all mechanical.

google it VW self study for pumpe duse ssp209, should explain it better than I can.
 

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I can see the same style adjustment on the camshaft too but I've never tried this and I don't have a CRD to test. If you have a common rail, try it out and let me know or see if you see the same values in torsion. I wouldn't be surprised if it did but I don't know.
 

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Hi, sorry for ressurect this topic, but i have a question, could't find anything anywhere I've searched.
I have an 99' Passat TDI-PD ATJ, and to adjust the timing I need to do the exact opposite of what you explain in this tutorial. When I turn the camshaft (18 mm bolt, not camshaft pulley) clockwise torsion value goes down(minus) and when i turn in anticlockwise torsion value goes up(plus), is it normal (maybe for longitudinal engine) or I have some issues? Thanks, and sorry for my typing skills.

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