The camshaft has to turn and should just like the other side does. I'd say you either have a broken timing chain or the cam sprocket to camshaft bolts have sheared off so the sprocket is turning but it's no longer connected to the camshaft. Neither of these scenarios are good so I hope it's something else that I haven't thought of.

 

Thanks Petza I might be wrong on driver side camshaft turning. In fact it's just that starter turns but I see no movement on the timing chain.

What could be the issue in this case?

 

Does the same thing on the opposite side turn or is that not turning either?

If neither of those is turning, it sounds like the Bendix on the starter may not be extending to turn the flywheel so you hear the starter spinning but it's not actually turning anything on the motor.

 

Please check the picture below to avoid confusion on what turns and what not.

 

Isn't that the water pump? The starter is at the back of the engine.

 

Thank you Brian. My engine knowledge stops right here It might as well be the water pump turning.
But I definitely hear the starter running for a few seconds before quitting.

So the theory that Bendix does not engage might hold water...

 

You're saying the timing chain isn't rotating with the starter, but the water pump is turning? The water pump is belt driven by a pulley from the serpentine belt, which is driven off the crankshaft. There's no way for the water pump to be turning without the timing chain turning everything on it (oil pump, cams, etc).

 

You guys are far more knowledgeable than I am. So,I would appreciate if you could have a look at the video below and guide me.
I captured the problem.

 

Well you described it accurately. Engine crankshaft turns, timing chain doesn't move.
That's really bad....
I suppose the timing chain is broken.
I think this is an interference engine. So there are going to be bent valves.
The next step? Probably remove the front timing cover.
Or, obtain another engine.

 

Thank you. I checked with my fingers the chain looks quite tight, do you think it is really broken? Guess I need to open the cover to be sure.

If it gives any insight. Initially the car was running but just starting at the second crank. There were no unusual noises from the engine once it started.

The other day I just parked after a long ride and it didn't start anymore despite the fact that I was hearing the starter running.

If it was the broken chain should not I notice while the car is running with strange engine noises? Would the chain be still so tight?

I am not very experienced in mechanics

 

I suppose it's possible the key linking the crankshaft sprocket to the crankshaft failed.
I think you need to remove the front cover to diagnose further.

 

TLDR: If you are having camshaft sensor error and having difficult starts, 100% of the time it is because of a broken timing chain tensioner.
It seems this is a frequently occurring issue for this engine, that the delrin chain guide gives up after about 100K miles and breaks into pieces.

Depending on your luck you get any of the following with increasing cost:
1. Just a broken tensioner
2. Broken tensioner and broken chain
3. Broken tensioner, broken chain and bent valves
4. All of the above plus damaged cylinder heads
And damaged cover, and sprockets etc.

Here's a demonstration of the problem:
https://fb.watch/nE75nnSJZI/

If you have this issue during driving the pieces may get stuck between sprocket and the chain. Pieces may go into cylinder block. Broken chain may hit the valve cover.

Below are the photos of my engine. I called a pro and he was able strip the cover in about 15 minutes without removing the radiator etc.

I may be lucky that my chain broke not while I'm driving but while I was trying to start. Chain hit the valve cover. There were metal chips from this. Crossing fingers that they didn't go into valves.
This guy recommended me to replace the complete set including sprockets etc. because you may have the same issue with other parts and next time I might not be lucky.
The cost of the set is about 600$ or euros. He reckons it needs 8 hours of work to replace all and adjust the timings.

Well I'm hoping this is the end of my story. I wish luck to you all having the same issue. I thank you all who helped me throughout the process.
Next time the first thing I would do in such a case would be to check the RPM indicator when starting. If it doesn't move, this means starter runs but engine does not.
Then I would open the oil cap to check whether chain turns or the chain is loose. I would also check if the water pump is turning.
BTW. in the earlier engines there is also the issue with camshaft adjusters.



No need to remove air intake or radiator to see the chain.


Valve cover had damage from broken chain

Scratch marks from broken chain

Broken valve cover

 

Also please check out the following thread, which I just came across:
https://rennlist.com/forums/cayenne-...r-of-time.html

 

Thank you for taking the time explaining your story in detail. In the end you are lucky. It could be much much worse.

 

That’s unfortunate but I agree that it was very nice of you to leave such a detailed explanation. Hopefully your damage is relatively minor. I wonder if this is an age of the vehicle issue that we’ll all be dealing with soon? Plenty of Cayennes with 200-300k driving around on original chains suggests that the guides just get brittle with so many years and heat cycles.