There is a great deal of secrecy and denial about cam chain problems on Tsi engines. Surprised? This is volkswagen group after all.

There are a number of issues.

1. Up to mid 2011 the newly adopted inverted tooth camchain design was weak, and the chains were sourced from a cheapskate supplier that used clapped out tooling to stamp out the links. The chain link pivots therefore wore quickly and the chain stretched. And that wore the sprockets too. Vw denied any problem until they had so many failures they adopted a silent recall approach that only addressed obvious rattling cases and then only if within warranty.

2. They attempted to address the problem on newer builds by changing supplier and using a different link configuration. They also put a simple chain guard in the cam cover that would limit how high the chain could ride off the sprocket. However, rattling chains on start up still occurred.

3. It became obvious there was also a problem with the hydraulic chain tensioner and this has be subject to a number of revisions over the years. Again, all secret.

4. The most contributory factor in my opinion is the arrangement of the oil filter. On the tsi this is a screw on cannister type that sits on the top of the engine, the base of the cannister uppermost. This design potentially gives the problem that if you unscrew it, it would pour its contents over the engine. However, some bright spark decided to design in a drain back valve located in the housing which opens when you unscrew it to release the oil to sump. Clever these Germans eh? Except this drain back valve is a crap design, and if the filter is under or overtightened, it doesnt seal properly, and it leaks anyway. So when the engine is switched off, the oil filter drains down slowly, and being a VW design the camchain hydraulic tensioner releases. So every cold start is like the oil has been drained.

Cold start, tensioner backed off, chain stretched, sprockets worn, empty oil filter, no oil pressure for 3 or 4 seconds. I wonder what might go wrong?

This I have learned the hard way over 4 years as I have tried to convince skoda dealer that cars shouldnt rattle like they have a clapped out engine on cold starts. Denial, lies, secret workshop instructions, seemingley incompetent mechanics and a group culture that force dealers to take the financial hit on warranty claims so the dealer is unwilling to do anything.

Welcome to Volkswagen Group.

Edited by brum on 24/01/2016 at 20:27