VW Passat 1.9TDI PD 2003 type - VW Passat timing belt fine tuning query (vagcom)

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Tue 11 Jan 2011 23:29
VW Passat 1.9TDI PD 2003 type - VW Passat timing belt fine tuning query (vagcom) - brianthnach

Hey guys,

Just completed changing the timing belt on a VW passat AVB type engine. All went well and its motoring along. I used the locking tools and did everything as per the book and took my time at it.

The car is going perfectly but I feel the engine is just slightly different than before and I mean slight. Ive over 300k on the car, no one else notices anything different, but I do. If anything I would have to say not quite as smooth (being very picky!!).

Ive connected up the vagcom by rosstech and everything is ok. It states that the syncro angle between the crankshaft and camshaft is -1.6 deg (minus). Now ive read on another site a good bit of discussion on this topic and many profess that passats are 'happier' in the 0 to 0.5 deg range, better mpg, smoother idler etc etc. Its just a matter for me of advancing the camshaft ever so slightly.

My main query is to find out roughly how much of a movement of the camshaft relative to the camshaft belt pulley would this require. i.e. would a movement of 1mm at the radius of the bolts correspond to a 1 deg change in this angle??

Im just being cautious as Im pretty sure this is an interference engine so dont want to go messing things up!! Im sure of the procedure etc. just not so sure of how much of a distance i would need to advance the camshaft at the diameter of the three fixing bolts to attain a 2 deg approx advance. I know its slightly nitty picky!! :)

Thanks for your help,

Jim

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Wed 12 Jan 2011 09:42
VW Passat 1.9TDI PD 2003 type - VW Passat timing belt fine tuning query (vagcom) - Peter D

Do you mean an engine code of AVF not AVB. After you set all this up and rotated the crank 2 complete turnes did all the markers line up. What manual did you use to obtain the information. Regards Peter

Edited by Peter D on 12/01/2011 at 09:50

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Wed 12 Jan 2011 14:06
VW Passat 1.9TDI PD 2003 type - VW Passat timing belt fine tuning query (vagcom) - brianthnach
Peter,

No its definitely engine type AVB. Its a 99 BHP engine. Everything lined up perfectly after rotating two complete turns and two more complete turns just to double check. I know it was done correctly.

However even with the lock down tools a small movement is possible on the crankshaft, now i do mean small!!

Spec for this syncro angle is between -3 and +3 deg so it is a fine tune really. Currently its at -1.6 degrees.

thanks

jim

Edited by brianthnach on 12/01/2011 at 14:07

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Wed 12 Jan 2011 14:26
VW Passat 1.9TDI PD 2003 type - VW Passat timing belt fine tuning query (vagcom) - brianthnach

Heres a link that offers some info on this topic;

www.myturbodiesel.com/1000q/multi/PD-adjust-Idle-T...m

I always use the ElsaWin manual. It doesnt detail anything about this fine tune however.

jim

Edited by brianthnach on 12/01/2011 at 14:35

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Wed 12 Jan 2011 15:24
VW Passat 1.9TDI PD 2003 type - VW Passat timing belt fine tuning query (vagcom) - Peter D

Ok I have found your engine AVB. I suggest you post this on www.vwaudiforums.co.uk and go the Audi forum and contact Crasher although I think he posts on the passat section as well. Regards Peter

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Wed 12 Jan 2011 15:40
VW Passat 1.9TDI PD 2003 type - VW Passat timing belt fine tuning query (vagcom) - 659FBE

The "torsion value" is adjustable in-situ as outlined by the first link. You need VAGCOM or similar to set it. Note that there is an error in this link - the 18mm AF bolt turns the camshaft and its hub - NOT the camwheel - which remains fixed by the belt.

I think more is made of this adjustment than is warranted. If you lock the engine correctly and recheck the locking, you are very unlikely to be outside the permitted +/- 3 deg tolerance. As the PD engine is very sensibly timed from the crank, the relative cam position is not too critical as long as the unit injectors remain fully pressurised over the whole injection advance range. The VAG setting tolerance takes account of this.

The torsion value will also affect the engine valve timing - but we are dealing with minute amounts. Other engines which were fitted with stretchy cam chains would change by far more than this during their life.

There is obviously a VAG "pinion" tool to adjust this as there are internal teeth in the wheel - but I've never seen it. Perhaps they never produced one. By all means fiddle with it but if it's within tolerance I wouldn't worry.

I have to say I've not even checked this on my PD following a belt change. It starts and runs properly with good economy - so I'll apply my mind to other things.

659.

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Wed 12 Jan 2011 16:47
VW Passat 1.9TDI PD 2003 type - VW Passat timing belt fine tuning query (vagcom) - brianthnach

I meant to mention that in the above post - 659 is correct - its also known as the torsion value. I was thinking there was such a pinion tool as well. Maybe it was just used to set from new??

It is a fiddling thing I know that. as it is within the +/-3 tolerance. You probably are correct that more is made of the adjustment than is warranted. Just that it is pretty easy to access Im a bit curious if it would be causing the slightest of an improvement to the issue I stated above.

Either way, I take it Im not going to cause any piston hit valve scenario by adjusting within the oval slots on the cam belt pulley? Bolts are central in these slots now.

cheers
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