KNOCKING SOUND FROM ENGINE OF CAYENNE S 2011
 

found another concern lately. There is a knocking sound as i accelerate from standstill or when driving slowly at high gear. The sound of knocking as if using a low octane gas/petrol. I am currently using Octane 98 so should not be the case. Anyone has encountered this sound?

hello there , i have the same problem in my 2011 cayenne s and till now they didnt have any soloution for this problem

execuse me , but what is ur location ?

:corn:

I have this exact issue. Sounds like low octane fuel, but I'm using 93. What is the issue? I did not have this 6 months ago. 2011 Cayenne S with 21k miles.

:corn::corn::corn:

Sorry, but what does that mean? Is this a known issue?

I've seen A/C lines tapping against the firewall cause a knocking sound on a 2011 Cayenne S, however I would definitely get it checked out ASAP to be sure it isn't an internal issue.

According to PAG, minor knocking, pinging or pre-detonation is somewhat normal on all V-8 equipped Cayennes. On some models, it's more noticeable than others.

Most owners don't even hear it however, start out in 2nd gear and drive slowly next to any wall or barrier with your window open and it'll be obviously noticeable.

I've heard it on mine (now 40k miles) a handful of times. It seems to occur after the car has been idling for a long period of time.

The knocking sound in my 2005 4.5L V-8 was scoring in the cylinder walls on 3 of the 8 cylinders. This was a known issue with PAG.

The scoring was a result of piston coatings transferring from the piston skirt to the cylinder wall.
The rings then bedded the material to the cylinder walls and caused low compression and knocking.

The result was a warranted long-block engine replacement to the tune of $14,000

I sincerely hope this is not your situation.

The only clear-cut way to diagnose is to bore-scope the cylinders and look for scoring.

If this is the case, your dealer will likely avoid and deny the issue is even a remote possibility until you make them scope it.

The issue seems to affect cold weather cars more than warm weather cars. If you are in a warm climate, then you are probably OK

:corn:

I had the same experience in my 04 CS. I'm considering a newer Cayenne; I hope this is not an ongoing issue even with the newer ones. Best wishes to OP.

The 4.8 engines have piston oil jets to cool and lubricate the cylinders. The 4.5 non-turbo motors did not. I suspect that such a failure is much less likely on the 4.8 because of this.
When I worked at the dealer, I saw about 8 4.5 non-turbo engine failures that all started with cylinder wall scoring. I saw no turbo engine failures. The 4.5 turbo has piston oil jets, so I figure that's what made the difference.

Sounds like Porsche service has high tolerance... brake squeaking is normal, fluid leak is normal as long as it's not dripped to floor, now even knocking is consider normal... :P

You're forgetting 1 ltr of oil every 650 mi.


....though mine uses less than 1/4 qt. in 7,500 mi.