LarryJa

This has to be most frustrating for you, because you had done everything quite correctly &, apparently, the replacement tensioner is now failed. It sounds like the tensioner just wasn't getting enough oil pressure to maintain it's function. . From what I recall, you did, even, prefill the tensioner with oil to shorten it's time until engine oil pressure came up.
Maybe, a gasket failure, or a slug of (doubtful)dirty oil that resisted it maintaining good prezsure, etc.
Very frustrating, but I'll encourage your pursuit of a successful completion.
You just need to find the frustrating cause.
You have worked quite diligently through all issues.

Sverige

Thanks Larry. I've now obtained a replacement tensioner and I fitted it today. Following this I hand cranked the engine two revolutions then could refit the cam locks and crank pin, so everything stayed in time at least. I observed exactly the same behaviour in the new tensioner while hand cranking as the last one, namely the piston collapsing with a click then extending again three times per revolution. I suppose this means it's either normal or I've messed up the installation of this new one in precisely the same way as before. Either is possible!

Tomorrow I hope to complete reassembly to the point where I can start the car and then I suppose I will find out if I fare any better.

Sverige

Today I got the car back together and started her up following my bank 2 tensioner replacement . So far, so good! It started with a chain rattle audible but that lasted no more than 2 seconds before it quietened. I left it to run for several minutes and there was no sign of the rattle coming back, which was the problem I had last time. Block 93 values look good (only bank 2 has been worked on, the bank 1 values match the "before" readings). After warming up, the bank 2 exhaust moved to -0.4 deg but intake stayed at 0.0.

Pretensioning the chain is an issue I've been very uncertain over, but for the record the approach I took this time was to leave the cam sprocket bolts loose enough that the sprockets could move easily (without wobbling from side to side), then pull the grenade pin, then manually rotate the intake sprocket (not with counterhold tool, just by grabbing it) so there was no slack between the bank 2 exhaust sprocket and the lower sprocket. No need to pull it tight, just to move the slack (if there was any) to the tensioner side of the intake sprocket. Finally having done this I used the counterhold tool to brace anti-clockwise on the intake sprocket as I tightened the bolt to 30Nm, then same again on exhaust sprocket (using the counterhold to support the exhaust sprocket). Likewise I proceeded to 60Nm and the final quarter turn, each time using the counterhold to prevent the chain between exhaust sprocket and lower sprocket from taking the tightening force applied to the cam bolts. I don't claim this is the right or best approach and it's too soon to be sure my repair is a lasting one, just putting this down in case it helps others.

My aim was to prevent the chain between exhaust sprocket and lower sprocket becoming stretched taut, as I still wonder whether that caused my first tensioner failure (Cnyman warns earlier in the thread about this).

hrc4u

Well done! Sverige! =)
cheers!/H

LarryJa

Wow!
I am impressed with your thoroughness & results!
Great job!

Sverige

Thank you for all your advice and support throughout H, I am sure I would not have had a successful result without the info you provided. I certainly took your advice to take it slow! Thanks also due to the OP and all you others who've added to this thread and we now have a great resource here which, viewed with the Edge Motors video, makes it possible for even a numpty like me to fix this Achilles heel on the 3.2 litre FSI engine.

My car is running great now and as stressful as it was at times, I am very glad I took this on and I certainly learned lots in the process. I'm sharing below the notes I created which I printed out and referred to as a guide. I've updated them to incorporate some of what I picked up, but please remember I'm no expert, so please cross check details and make sure you know what you're doing by watching the Edge Motors video on YouTube. .
The timing chain bolts are tough to get at. I actually found a little $10 mini ratchet set from Lidl (pictured) came in useful time and again while doing this job. A 60cm breaker bar is pretty essential for the final 90 degree turn on the cam bolts and take HRC's tip of exchanging the counterhold tool's pins for M8 bolt plus nuts, as these grip the cam adjusters much better. Hardest part of the job was getting the crank pin hole plug out. That and getting the sodding belly pan back on - but that's the hardest part about doing anything on these cars!

Below sequence is written with Bank 2 in mind (driver's side US/continental Europe - passenger side UK, Aus, etc..)

1. Remove plastic engine covers and move coolant tank & wiring loom out of way
2. Remove coilpacks (air box or air hose from air box needs to be moved from bank 1 side)
3. Clean with air around valve and cam covers
4. Remove vacuum hose then cam cover bolts and cam cover
5. Remove bracket from back of oil filter housing holding electrical connectors (10mm socket - remove nut, then oil pressure ground cable, then remove stud with same socket).
6. Remove timing chain upper cover & inspect chain and tensioner piston
7. Remove spark plugs (use rags to cover holes) then rotate crank 3-4 complete 360 degree rotations then rotate to put engine in TDC
8. Lock cams with cam locking tool plus 1/2" extension
9. Insert crank locking pin (drop sway bar for access)
10. Loosen bolt on intake (upper) cam adjuster
11. Loosen bolt on exhaust (lower) cam adjuster
12. Remove bolts and then cam adjuster sprockets
13. Remove T30 bolts and take out tensioner.
14. Remove tensioner gasket if still in chamber
15. Inspect and clean area then install new tensioner, 9Nm torque on bolts (fill new tensioner with oil)
16. Install intake sprocket then insert bolt by hand until sprocket can rotate but not wiggle
17. Install exhaust sprocket and insert bolt by hand until sprocket can rotate but not wiggle
18. Pull grenade pin on tensioner
19. Pretension chain by rotating intake adjuster clockwise, any chain slack to be on tensioner side of intake sprocket. Sprockets must be able to turn freely (not stiff) at this stage.
20. Tighten intake sprocket bolt 30ftlb using counterhold tool on intake in anti-clockwise direction so chain isn't tightened further
21. Tighten exhaust sprocket 30ftlb using counterhold tool on exhaust in anti-clockwise direction so chain isn't tightened further
22. Test chain tension with fingers pressing perpendicular to chain direction. Should be minimal movement between sprockets, tiny movement if pressing chain sideways below exhaust sprocket and a little movement in unsupported stretch of chain between tensioner arm and intake sprocket.
23. Tighten exhaust sprocket 60ftlb with counterhold tool holding force applied on exhaust sprocket in opposite direction
24. Tighten intake sprocket 60ftlb with counterhold tool holding force applied on intake sprocket in opposite direction
25. Tighten intake sprocket bolt final 90 degrees with counterhold tool holding force applied on intake sprocket in opposite direction
26. Tighten exhaust sprocket bolt final 90 degrees with counterhold tool holding force applied on exhaust sprocket in opposite direction
27. Remove cam locking tools
28. Remove crank locking pin
29. Rotate crank two engine revolutions and check all runs smoothly. Clicking from tensioner piston 3 times each rotation is normal (engine feels stiff to turn directly after each click).
30. Reinstall cam locking tool and then crank pin (to test everything still in time)
31. Remove cam and crank locks and replace crank lock plug with 6mm hex key
32. Reinstall sway bar (25Nm torque on nuts)
33. Reinstall timing chain cover with rtv - torque bolts in numbered sequence to 5Nm plus 90 degree turn
34.Reinstall electrical bracket below oil filter housing. Longer end of stud passes thru flat lower bracket, then upper bracket with 90 degree lugs, then screws into engine block. Next fit oil pressure ground cable then final nut.
35. Reinstall valve cover with 9Nm torque on bolts in numbered sequence then connect Vacuum hose
36. Reassemble spark plugs (25Nm), coil packs, air box/hose, wiring looms, coolant tank & engine covers.
37. Start engine, ideally with vcds connected and block 93 values displayed

Newbie123

Hi Sverige,


Background- I had code P0439/ Cam position sensor error/bank 2. On top of that, the A6 was cranking longer than usual to start with the rattling noise. Once running, the engine was smooth but did seem to lack a bit of power. So I disassembled the driver side. I just put the crankshaft locking pin in. Now I am stuck. I believe that I may have jumped a tooth on the the drivers side cams. With my crankshaft TDC pin in all the way, the drivers side camshafts holes are off just enough that I can't get both bolts for the locking bar in. This is why I believe that I have jumped time. So here is my question- Do I proceed to undo the camshaft adjusters, replace the tensioner and then align the camshafts as I reassemble?
If yes, How would I hold the camshaft adjuster while I unbolt it without the cam lock installed to countering the force I need to apply to remove the camshaft adjuster?

Thanks in advance for any help you can provide.

Thanks in advance for your help.

Sverige

Hi, did you watch the Edge motors video? The situation you describe appears to be exactly what he was faced with. He pinned the crank then took the cam adjusters on bank 2 off without the cam locks in place because it was out of time and the cam locks wouldn't fit. You would use the counterhold tool to brace against the torque as your loosen the bolts so the chain and camshafts are not stressed.

Also, using a 1/2" extension as an improvised cam lock could be a good option for you, as in this Russian guy's video:

Good luck

Newbie123

[That was meant to be joke right? I am referring to wedging a 1/2" extension in between the camshaft and the head? Unless I am missing something, thats what it looked like he was doing. QUOTE=Sverige;25072275]Hi, did you watch the Edge motors video? The situation you describe appears to be exactly what he was faced with. He pinned the crank then took the cam adjusters on bank 2 off without the cam locks in place because it was out of time and the cam locks wouldn't fit. You would use the counterhold tool to brace sion against the torque as your loosen the bolts so the chain and camshafts are not stressed.

Also, using a 1/2" extension as an improvised cam lock could be a good option for you, as in this Russian guy's video:

Good luck[/QUOTE]

Sverige

I didn't think it was a joke, but I could certainly be wrong of course - there's a semicircular indentation in the camshaft into which a 1/2" extension fits exactly, and given he's in Russia and seemed to have made a number of the tools himself, I took it to be an improvised solution which might help in the situation where the cam locks don't fit exactly. However my recollection is that in the Edge motors video he simply used the counterhold tool to help remove the cam sprockets on the bank 2 side which was out of time, so hopefully that remains an option for you?