Yes it is back. On my last oil change i have switch from Mobil 0W40 to Castrol syntec 5W40. There was no more lack of oil pressure on start until last week....Did around 500 miles with this new oil and the growling is now there at every cold start.. The tsb 1728 was done twice to be sure this valve was not at fault but no success......Really discouraging....


http://www.youtube.com/watch?v=dyWxfZ_MGBs


http://www.youtube.com/watch?v=NJpN0n2F57o

 

thats normal... what are you worried about?

 

I'm a bit without word Marski! I know you are a very competent Porsche specialist but I am surprised to see that you don't seem worried about the fact that there is a lack of oil pressure on start and where this noise come from????? Especially it happen only when the engine did not run for one or two days....

 

I watched the videos and thought, did I miss something ?

I'm not nearly as distinguished as Marski, what the hell do I know.

 

You both surprise me. Of course I only heard my own car. And having this noise only in some occasion ....Then I'm sorry about that but of course I feel better....Thanks for your input JS and Marski, I feel a bit stupid but if you don' ask you don't know

 

I listened to the start up and heard nothing wrong. I did not watch your gauge.

 

Looks fine to me. You are getting oil pressure within 1 or 2 seconds of startup.

 

Both clips sound and look normal to me. Looks like your oil pressure gauge spikes up to full once you get ignition. Not sure what your concern is at least from those clips....

 

That is how my car sound on every start, so I hope is normal .

 

According to the TSB, the valve is designed to close upon engine shut down to prevent the oil tank from emptying into the crankcase. I'm assuming in normal operation the valve opens when the engine is running. If the valve failed in the closed position then oil would stay trapped in the oil tank and thus starve the engine of oil (hence the warning to not leave the engine running while trouble shooting). If you look at your second video, the valve must be opening properly since you are getting oil pressure within a second or so of engine rotation. I don't believe you will see oil pressure rise any quicker than what your seeing. The noise you hear initially is probably that of a dry engine before oil pressure builds up since most of the oil has drained off the internals due to sitting for a few days.

 

Same noise here. Pretty sure it's normal? All the other 996TTs I've heard sound the same way.

 

Thanks for your input everyone. I was concern since the noise disappear for a while.

 

I would not consider what you are seeing as normal. Your engine is taking several second to start building oil pressure. The noise you are hearing for about 2 second after the engine starts is the hydraulic lifters tapping due to no oil pressure. The only time you should expect to see/hear that is the first start after an oil change.

My car starts to build oil pressure as soon as I hit the starter and continues up after the engine fires. My oil pressure never goes to zero during the start-up and has no lifer noise.

You can avoid it even on the first start after the oil change by pulling the fuel pump fuse and spinning the motor with the starter for a few seconds. That's a different subject though.

 

I have the same exact sound on mine. Only happens when the car sits for a few days. I hope it's normal! Can anyone else chime in on this?

 

I'm willing to bet that your car did not have this "problem" for the most part when it was cold(er) outside. I believe this problem manifests itself more when the outside temps are fairly warm because when it's hot the oil stays thinner longer after shutdown and drains more easily off of your valves, lifters, etc. Also, your ims chain tensioner will leak down a little quicker when the oil is thinner and the sound you hear for a brief second or two is a combination of the lack of oil on your valves and lifters but for the most part it is the rattle you hear as a result of the slack in the timing chain. As soon as oil pressure builds in that 1 or 2 seconds, voila, slack in the chain is gone and the noise is gone. In the winter, or with colder outside temps, after you shut down your engine the oil will become thicker faster and will be less likely do drain off of the engine internals and will also prevent your chain tensioner from leaking down as fast. GT3 guys have this also....