RSbob

08 S 74K miles, oil is full and changed every 5K. Started developing a few second tick at cold starts. With the bore scoring phenomenon with these engines is this enough to be concerned or only until it becomes constant?

rsinghal3

I would not be concerned until oil consumption increases or blackened tail pipes. My guess is maybe the injectors are sticking at startup possibly?

Petza914

I don't know the Cayenne engine well enough, but this problem in a 997 is failing timing chain tensioners. They're both spring loaded and hydraulic. When they go bad, they allow the oil pressure to bleed out and you get a tick or rattle like this until they repressurize. It's bad because it allows the chain to slap and rattle against the plastic paddle guides, chipping away the guide plastic. I would look into new tensioners sooner than later.

RSbob

Much appreciated.

deilenberger

Or look into an oil change with an oil that drains back more slowly, and has a higher cold viscosity. I'd try the Pensotin 5W-40. My CTT seems to love it (engine very quiet and no oil use at all..)

RSbob

Dam-n. Recently bought 20 quarts of Mobile 1 0/40. Pentosin sounds like a more cost effective first step worth investigating. Oil change is due in < 400 miles. Thank you

deilenberger

Certainly worth a try - Mobil 1 has been claimed to thin out with miles on it. I seem to remember heated discussions on Bobs the Oil Guy about that... and I've seen it in Blackstone reports people posted here and the ones I had run.