bparks

Car is a bonestock 2001 996TT with 60K miles.

Sometimes when I start the car after it has been sitting for 4 days or more, for the first 2 seconds the oil pressure gauge will read zero and the engine noise is rough and loud. Then the gauge zooms up to 4.5 and the engine note smooths right out. Engine runs fine otherwise.

The car has had TSB 1728 Lack of Oil Pressure on Start Up completed, with the new check valve PN 996.207.012.74 installed.

I’m just wondering if this is typical behavior or something I need to resolve. I've searched the forum and couldn't find a similar post.

Bos

FWIW... Can't really comment about the oil level concerns, but the car will run a little louder until the cats warm up.

Joe Weinstein

Can I hazard a guess that it's cold, and you're running thick oil?

manny_g

you should probably look into it further. this has never happened to mine, 03 tt with 41k miles.

rwilliamtaylor

2 seconds with 0 oil pressure is never good, especially when it sounds bad too!

Mine is a bit louder for about 10 seconds on cold start up, but I believe that is an air pump for emmisions and normal.

bparks

This only happens when the engine is stone cold, regardless of outside temp (it's rarely hot here in upstate NY). Oil is 0W40 Mobil 1.

Joe Weinstein

OK, that's thin enough to flow quickly to where it needs to at startup. I am
now out of my depth, and will defer to motor guys.

Chris Ward

Doesn't sound right to me....

I'd get some oil flush and get that through it, then change the oil filter, and fit a quality oil like modil 1, I use mobil 1 15/50 racing oil

Bos

Just commenting... Mobile 1 0W40 is current Porsche "standard".

Chris Ward

Any OPC will fill with mobil 1 15/50 racing oil if you ask them, no problem..

Comes in the same looking can just with brown background that's all..

WCE

My car does the same thing - at least the lifters don't clatter like my beemer.
Never heard of this TSB - do you know if it applies to later models?

bparks

TSB 1728 Lack of Oil Pressure on Start Up is dated 7/27/00 and states:

Vehicle Type: 911 Turbo (996)
Model Year: As of 2001
Concern: Oil pressure light on, lack of oil pressure when the engine is first started.
Information: Due to the low position of the turbo-chargers, a non-return (check) valve is installed between the oil tank and the engine. This prevents the oil tank from emptying into the crankcase when the engine is turned off. In certain cases, this valve could stick in the closed position. This would prevent the flow of oil from the oil tank to the engine. As of May 18, 2000, a modified non-return (check) valve is being installed from engine number M96/70 - 64 1 01282. The new part is identified by a light blue paint dot.

So it looks like early 2001 models may not have been built with the modified check valve. Mine has it. Mine also does not have the engine oil light on during this initial period of concern.

I was hoping other owners might at least comment on noises their engines make during the first second of two. Maybe the noise I hear is something else, like the air pump that rwilliamtaylor mentioned.