Broken Swirl Pots and Lots of Trash in the Sump

2003 996 w/ 210k miles In the spirit of sharing interesting things that can go wrong with these cars ... I pulled the sump plate off my car today chasing some weird oil pressure issues and misfires on bank 2. I discovered some exciting plastic trash in the bottom of the pan! It looks like large chunks of the "swirl pots", i.e. oil separators broke apart, especially where the diagonal tubes connect. I'm assuming the brown plastic is wear from the timing chain tensioners. I'm hoping that most of the black plastic is from the swirl pots and not the timing chain guides. Both swirl pots were clogged with black plastic chunks. I was getting occasional low oil pressure warnings at idle, when the engine was warm. I just assumed it was a faulty oil pressure sensor that typically goes haywire on these cars. I'm thinking the clogged swirl pots would contribute to an actual low oil pressure warning? I'm not sure what would cause the swirl pots to break apart like this? Although after 210k miles the plastic does feel a little rough and brittle.

How does the pickup tube look? Is the screen clogged?

The pickup tube is clean. Nothing on the screen so I don't think much if anything got sucked up.

I found tiny pieces of brown timing chain guide and some silicone in my screen when I dropped my sump. I had slightly better oil pressure after I cleaned it out and installed my deep sump. I wonder if yours was clogging but then the pieces dropped back down when still. Also with broken swirl pots you may have had excessive aeration of the oil.

Thanks for your thoughts. Makes sense. A good majority of the plastic bits were down in the pan directly below the pickup tube. They�re probably heavy enough to drop back down when the engine is off. I�ll have to do some research on excessive oil aeration.

Most all those black plastic is from the chain guides. What happened was piece of chain guide stopped up the return tube and that backed up the pressure and when the pressure got too high it busted the plastic tube...

I�ve read about tensioner and guide debris clogging up the swirl pot tubes. So � how much debris is a concern? Hard to tell how much is guide and how much is swirl pot. i know the guides and tensioners were replaced at 202k miles. Is it normal for new guides and tensioners to shed material? Or maybe this is leftover from the old ones they replaced � My cam deviation values seem ok. Bank 1: 2.04 and Bank 2: 0.98

If they were recently replaced then you're OK !! Yes the return tubes were probably almost stopped up before they replaced all the guides and they failed to find it . And a good bit of guide debris can hide in the engine... When it finished stopping up is when it busted the tube.... You will probably be ok after you clean out all the crap. ......What kind of oil pressure issues were you having and for how long/often??

Yeah seems like the sump plate hadn�t come off in a good long while so likely they never looked in there when replacing the guides. Two oil pressure issues: after driving a good bit and running it at temp, the car would occasionally flash a low oil pressure warning message when stopped and idling. I�ve also started seeing an occasional indicator failure warning but figure that�s the pressure sensor going out. I�m running Mobil 1 5w40 I�m also chasing some misfires on bank 2 below 4k RPM. Seems to be variocam related. It misfires like the timing is off. I�ve changed both variocam solenoids and all coils & plugs. I�m thinking it might be bore scoring but before I go there � I�m wondering if the oil pressure is restricted or I have plastic bits in the oil passages that might be affecting variocam operation.

There are updated air/oil separators (without the chamber pot) on the M97 that will fit the M96. they look like these: (mine came with my LN 2qt deep sump kit, but I think I’ve spotted them for sale on LN’s website by themselves)

Here they are: https://lnengineering.com/products/p...turn-tube.html

Yeah I saw the upgraded 997 tubes. I like the Keep it Simple thought. I wasn�t sure they would fit on a 996. Thanks for confirming that. I should be able to look up the part number from a diagram and order them. edit: Great! Thanks for the link.

If I were you I would install an analog manual oil pressure gauge and test the actual pressure when hot at idle and above 4k to see exactly what you got.. vario-cam on 3.6 can be greatly effected by oil pressure,,,too much or too little and it will not work correctly..

Ok thanks for confirming my suspicions on oil pressure and variocam ops. I imagine variocam is sensitive to viscosity too. Good idea in the manual gauge. I�ll search on how to do that.

�after driving a good bit and running it at temp, the car would occasionally flash a low oil pressure warning message when stopped and idling. � this happens to me as well when it�s hot outside. With the AC on it does not happen as the ideal is kept slightly higher.

Quotes source post: 18498060

...or the engine is cooler because the radiator fans are on with the AC.

Those pieces would make a beautiful collage/mosaic piece of art

I'll preserve them in resin and hang them from my rearview mirror. The orange specs will reflect the sunlight well LOL New drain tubes to replace the swirl pots are inbound. We'll see how the car runs once installed later this week.