Engine timing parts?

A6 All/ S6 All
#1

Gearing up for my engine drop and reseal, Im getting together some parts in the shopping basket for what I may need (upper O2 sensors for example as preventative maint).
I need to measure using VCDS the cam to crank phasing. Talking to the S8 program designed, he said the phase angle OBD flag was moved to 8 degrees, past that you get a CEL, with 8 degrees of out of phase being already far past the chains useable life.
So naturally I am looking for chains, all 4 chains will be $480. Then I got to thinking, what about the adjusters…No where on the audi parts websites so i see the timing chain adjusters/tensioners listed. Anyone got a link or some PNs?

Will measure my phase angle this weekend though so see if I even need to worry about this. (channel 90-93 IIRC?)

#2

Interested to hear about the phase checking…

Will be doing a motor pull soon as well.

#3

So you’re saying there’s actually a way to check the chain stretch by looking at this phasing value to determine it’s w/i spec? Wow.

#4

Thanks, I copy/pasted that to the shop that generally does the work on my S6.

#5

Looks like there are two upper tensioners and two lowers. Part #'s from what I could find are:

Upper: 079109217R & 079109218R

Lower: 079109507AF & 079109507M

Hope that helps!

#6

Cam phase will very and the phase amount changes often depending on what’s requested say over lap or advance max negative etc etc.

If the TARGET REQUEST Vs ACTUAL is off more than 8 degrees that will trip a CEL. But logging isn’t directly going to tell you if your chains are stretched. and if phase is out of spec it could also be a long list of things from bad adjusters, bleed down tensioners and broken guides.

The likelihood of having stretched chains isn’t very good. Its definitely not a common issue. Not to say it can’t happen but its not something you see.

#7

Thanks for the clarification justin. Still a good item to check to see of any possible timing problems. If you are approaching the 8 deg mark, clearly something has to be up which would require further diagnosis. Can you confirm which channel this is?

#8

Looks like block 90 and 92 will show you commanded vs actual for at least intake cams (int and ex use same chain so will give you general idea.)
Ideally at idle or any condition really, we are not much further out than 1 degree from commanded to actual yes?

http://www.ross-tech.com/vag-com/m_blocks/090-098.html

#9

As usual, most of the blocks that work on all other audis dont pull up the right info for the s8.
I think i am alright though, 023 and 024 both show 0 fro block 3 and 4,
090 shows -22 deg block 3 and -22+0.5 block 4 at idle,

Ditto to 091,
092 blank
093 block 1 is -1, block 3 is 0,
094 block 1 19.5-20
094 block 1 19.5-20

#10

Its always good to check and you can’t be too safe. you just want to remember that phase is variable its looking more at actual vs requested. and remember it can be closer at some rpms and further away at others.

#11

92 93 would be good blocks to look at.

#12

So block 92 doesnt show anything. I will log the available channels to see what commanded vs actual is while driving and under various loading conditions and not just idle/low load free revving

#13

Sorry you have that duel ecu set up. On my car its 92

On yours is it 90 91 and 93…

I think there is one more measuring block in the 115 range that is or should be helpful as well.