986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post - Knocking sound from low-mileage Cayman (with clip!)

ChimpanZed · 07-09-2012, 09:44 AM

Hey All,

I'm experiencing a vexing issue on my 2006 Cayman S with just 7300 miles on the odometer.

It's making this sound

The sound started right after I changed the oil (5W-40 - same weight and brand what was in the car before: Pennzoil Ultra Euro). I filled the car with 8 quarts of oil (usually enough to get the oil level gauge to one of the middle bars) and started the car. I got a very brief "oil pressure low" or similar warning on the dash readout which went away in a second or less. I assume that it simply took a moment for the oiling system to purge the air from it. I let it idle then topped off the oil.

Shortly after I noticed the sound. At least I think so, I do not recall the sound before changing the oil.

I attempted to diagnose the problem myself to no avail, and brought it to an independent Porsche specialist for inspection. They replaced the oil pump pressure relief piston (a known issue and TSB) but that failed to fix the problem. They have been unable to definitely determine the issue, but noted that using a 0W-30 weight oil drastically reduces the noise. This corroborates with my observation that with 5W-40 the noise worsens as the engine and oil warm up.

I'm inclined to think that it's a sticky lifter as oil thickness/temperature correlates with noise, but it seems too intermittent to be a fully stuck lifter. The shop recommends driving it gently on 0W-30 for a while to see if the problem goes away.

Any direction is much appreciated!

07-09-2012, 09:44 AM	#1
ChimpanZed Registered User Join Date: Jul 2012 Location: Houston, Texas Posts: 5	Knocking sound from low-mileage Cayman (with clip!) - professionals are stumped Hey All, I'm experiencing a vexing issue on my 2006 Cayman S with just 7300 miles on the odometer. It's making this sound The sound started right after I changed the oil (5W-40 - same weight and brand what was in the car before: Pennzoil Ultra Euro). I filled the car with 8 quarts of oil (usually enough to get the oil level gauge to one of the middle bars) and started the car. I got a very brief "oil pressure low" or similar warning on the dash readout which went away in a second or less. I assume that it simply took a moment for the oiling system to purge the air from it. I let it idle then topped off the oil. Shortly after I noticed the sound. At least I think so, I do not recall the sound before changing the oil. I attempted to diagnose the problem myself to no avail, and brought it to an independent Porsche specialist for inspection. They replaced the oil pump pressure relief piston (a known issue and TSB) but that failed to fix the problem. They have been unable to definitely determine the issue, but noted that using a 0W-30 weight oil drastically reduces the noise. This corroborates with my observation that with 5W-40 the noise worsens as the engine and oil warm up. I'm inclined to think that it's a sticky lifter as oil thickness/temperature correlates with noise, but it seems too intermittent to be a fully stuck lifter. The shop recommends driving it gently on 0W-30 for a while to see if the problem goes away. Any direction is much appreciated!