Hi does anybody have any ideas / help.

I had an engine management warning light come on in my 2009 Octavia 1.4 tsi (40'000 miles) took it to the dealer and they could not find anything wrong mechanically so concluded a faulty camshaft sensor and replaced it and gave me back the car. 8 miles later the light comes back on, so back to the dealer a day later by which time the light has gone off. Computer has recorded a fault code that suggests problem between camshaft and crankshaft sensor. They checked the car again found nothing wrong having contacted Skoda and performed the requested tests. So return the car me. 10 days later the light returns. The car goes back in for quick inspection and the conclusion is it must be in the timing chain area but is safe to drive while it's booked to go in again. Having driven it for a few days while I wait the light is now on more than it's off, but does go on and off without any noticeable pattern. Car has suffered no apparent loss in performance during the whole process.

I'm now waiting on more dealer discussions with Skoda before a decision is made where to go next. Has anybody seen this before or have any ideas of what might be wrong ?

As a casual post viewer (not especially mechanical), I'd think that your camshaft drive chain has become worn.

 

The crankshaft and camshaft sensors are expected to be aligned/synchronised when monitored by the engine management computer. If they are outside the expected timings then the engine ecu will post an error complaining about the sensor, even though the sensor is working ok. 

 

The only way they can change their relative positions is if the cam chain has worn. It sounds as if your engine is on the border of producing this error, and so the light is intermittent at the moment. As the chain wears, this is becoming more permanent.

 

Some VW group 1.4 tsi engines have had cam chain failures, not very common though. (Ignore any problems on the web with 1.4 tsi Twincharger engines - they have their own faults and that engine was never fitted to your Octavia!). The factory admitted a quality control problem with some early chains in a foreign magazine report that I read somewhere on the web (sorry can't remember where).

 

If it is this, and it fails completely in use, it'll be a hefty bill, as the engine will likely be ruined.

 

I would expect the garage to recommend fitting a new cam chain and tensioner next.

 

Happy to be corrected by someone who knows more about this.

 

The same situation happened to some 2003 - 2006 Nissan 1.5 and 1.8 petrol engines IIRC. Cam chains were replaced on those engines as the cure.

Edited 13 May, 201412 yr by CombatWombat