Strange ticking sound (video)

[heiki]

Car did drive fine at first. The problem started few days after cambelt was done (about 300km/200miles)

Just few seconds, and the following codes appear and engine light was blinking:
17755/P1347/004935 - Camshaft Position Sensor 2 (G163) / Engine Speed Sensor (G28): Incor. Correl.
16684 / 16692 / 16690 / 16691 multiple misfire.

Cambelt hasn't jumped, but the tensioner was at it's bottom position and belt between cams was loose, but after about 1/4 turn from crankshaft, it regained it's tension.
Sound comes from right side of the engine for sure.

Compression values are measured ok, so it can't be the valves?

Here's link to video:
https://www.dropbox.com/s/e2svz12rlxc8q ... .50.56.3gp

Thanks!

[bilko1]

If you have incorrect correlation between engine speed sensor and cam sensor you have a timing issue. Could be timing belt or maybe cam chain / chains.

[Shoppinit]

Did you use the proper cam lock tool when you changed the belt?

Has that code gone away since you tensioned the cambelt correctly?

You need to check the timing again. Might be that a valve is just kissing a piston - not enough to damage it (yet).

For a start you can log the variable valve timing to see what values you get.

Log measuring block 90 values at idle and tell us what you've got.

[heiki]

Here are the values at idle rpm (Engine load ~22%)
Group 90
from -1 to 0
from 5 to 11,5 KW

Group 91 (Intake Bank 1)
Adjustment bank 1 value from -0,5 to 0 KW

Group 92 (Intake Bank 2)
Adjustment bank 2 value from 5 to 12 KW

Group 93 Phase position Bank 1 / 2)
Phase position 10 KW

[Shoppinit]

Wow, could you possibly make it any less clear?

[heiki]

Sorry, is it more readable now?

[grizz]

A worn cam chain or fault adjuster .

[heiki]

How to define if it's chain or adjuster?

ps. Proper cam lock tools were not used during change..

[Shoppinit]

You have to do the cambelt again with the proper tools. The timing is completely out. There is mechanical contact. Another degree out and you would have killed your engine.

Don't run the engine again. Get the cam and crank locking tool and do the job properly. If you are very lucky, no permanent damage has been done.

Don't forget to tension the belt properly by releasing the cam pulleys and resetting them, as the procedure calls for.

[Daveperc]

And do the chains and tensioners at the same time. Not cheap (tensioners about £280 each IIRC) but not worth the risk of them going. If either the chain or tensioner is worn you need to replace both.

Afraid you have one costly foul up on your plate. I would seriously consider cutting your losses by getting the car out of the place that has screwed it up, and getting it to either MRC or Unit 20, let them give you a report on what's wrong, and then decide whether to replace the engine or simply to repair. Meanwhile I would demand a full refund from your garage.

Good luck

Dave

[rob8457]

by the sound of it, i think you may have bent a valve mate, this is going to cost you dearly, as above get a refund as they clearly have not done this work before on the RS6
Wish you good luck also
Bobby

[heiki]

Plastic guide on tensioner is completely gone, as seen in image.
Guides can be bought separately from ebay etc, or should I change complete tensioner?

Is there way to check that valves are ok?

[imacool]

Check the valves? Heads out, which means the engine out.
Maybe using a borescope camera would help to check the valves, but not sure, the view is limited and you would need a very flexible cord to bend it upwards inside the cylinder to see the valves.

[bilko1]

Chain guides normally wear due to slack chains

[heiki]

Next plan is to change guides and chain, is there anything else that should be done at the same time?