Derek Michaels

I’ve been searching and am finding mixed messages. I had magnetic metallic dust or powder in the filter on my last oil change. 1999, IMS changed at 72k, currently 82k. I drive it hard, including 2 track days at 80k (instructor group) and I have no idea about 0-79k life. Zero flakes, only the dust. Runs smooth as silk. Pics attempting of filter and remnants from the magnet I ran over it.

JTT

I went through this a few years back. If it is ferrous as you mentioned, there are limited places it can come from. My investigation worked backward from the filter, checking the path of the oil for traces. In the end it turned out to be the IMS bearing (mine had also been replaced prior).

Do you use a magnetic drain plug? If so, did it catch any? I’d drop the sump plate to have a peek in there (very simple job to DIY).

Weazer

Agree with JTT above, very few places in an M96 engine for ferrous flakes or particles to manifest. Oil pump gears grinding each other away? Not likely but easy enough to check. Cam lobes grinding away at lifters? Also not very likely and a little tougher to check. Cam chain tensioner rails grinding away at their pivot points? Unheard of and, yes, very difficult to check. IMS or cam sprockets grinding away at the cam chains? That would probably make one helluva racket and, again, difficult to check. IMS bearing grinding itself, and the rest of the engine, into oblivion? Most likely scenario in an M96 engine. Remember, even though the dual row bearing used in the 1999's was more robust than the later single row, they do still fail. You mention that the IMS had been changed 10K miles ago prior to your ownership. Maybe the replacement bearing was defective, or the installation was sketchy. Consider yourself lucky, you've been given notice that something is amiss and its most likely with you IMS bearing. I would IMMEDIATELY replace your IMS bearing, maybe consider an upgrade. I put a Vertex cylindrical roller bearing in my 1999 Boxster base, 5 times the load capacity and I was very happy with the result. Was going to do the same to my 1999 C2 Carrera, however, when I dropped the tranny I discovered a replacement engine with the unserviceable large single row bearing had been previously installed. Best of luck.

808Bill

Sorry to see this. Whats the date of the IMSB replacement and with what brand? Do not start it again! Drop the sump and post a picture.
Many have had IMSB failures, replace the bearing and sell it immediately to some poor soul thinking he's good to go...

Derek Michaels

It was oem parts performed by a Porsche dealership here in CT. I have all receipts. RMS and IMS seals were done at the same time. I bought the car with 78,500 miles, changed the oil right away.

I agree, most likely is IMS.

If if at the track it went low pressure briefly would that contribute? The powder (think brake dust) seems inconsistent with nearly every post out there for IMS issues that show flakes, but I’m not going to chance things.

For it the drain plug, it is not magnetic, but I ran a magnet over the filter and that’s how I collected the small amount of “powder” shown in one of the pictures. It’s not much but it’s undeniably ferrous metal.

Derek Michaels

And it was 2016 replaced. I bought the car 3/2020.

lowpue

I had a piston rod bearing failure a few years back....are those bearing ferrous? If so, it could be that as well. My symptom in that case was an occasional puff of smoke on the track after a long sweeping right hander...eventually the engine blew up on that same long sweeping right hander

Derek Michaels

The first track outing I brought her to (Limerock), I topped off the oil and it was burning oil significantly after sitting and restarting before each following session. That went away as soon as I got home and drove a couple miles normally. Seems like that is common with oil filled to max

second outing at Palmer I had it at mid oil level. Ran flawlessly, zero smoke, but had a stumbling idle at the end of the day. Swapped plugs and coils, idle cleaned up to silky smooth. But given the turny track, with some compression zones (right turns in the layout I ran that day), I do wonder if I got low oil pressure a bit and caused something to wear. I’ve put about 40 miles on the new oil so I’m thinking pull the new filter and drop the pan to see if there’s more metal. Assuming yes, off to the local shop I trust

foe the dealer work, thoughts on them warranting their work in 2016 if it is the IMS? 10k miles with the dual row seems exceptionally soon for an issue.

Porschetech3

Not a chance !! , The warranty period for Porsche replacement parts/labor is 2 years with unlimited mileage. Any "goodwill" help will be dependent on whether you are precieved and a past good customer AND believed to be a even better future customer.

Mike Murphy

I would only add that 99s are 5-chain engines and suffer from premature cam tensioner pad wear. I would ask OP to check cam deviation and consider any non-ferrous brown or black bits that would show up in the oil filter to be related to these pads. Even though none is showing in the filter today, it could have in the past. If, and it’s a big if, the pads are very badly worn, the chain can start digging into metal parts of the engine. If the pads are that bad, the cam deviation would show it, and you’d likely hear a lot of noise upon startup.

theprf

I'm sorry to hear of your difficulties. Those are my 2 favorite tracks right now. I hope you get it squared away and that I see you out there next year!

Weazer

Lowpue, rod bearings and main bearings are copper with a tin "jacket", both non-ferrous materials.

Derek Michaels

A bit of an update and some additional info. I pulled the filter a few mins ago. The new oil has about 100 miles on it before I parked it. No noticeable metal, but more non metallic green pieces. They’re brittle. Can split one with my fingernail. Picture attached.

DreamCarrera

A Porsche dealership changed out the IM$ bearing in your '99 996? Did they extract the old bearing with the engine still installed in the car? I thought Porsche dealerships wouldn't perform this type of replacement work. In the past, P dealers considered the bearing a part that could not be serviced. Has this position, long held by Porsche, changed?

This is why I would not change a double row bearing (I have not and will not touch the bearing in my early 2000 build C2). It seems to me we are hearing more and more reports of replacement bearings failing. If this is indeed your replacement bearing failing, I would bet the original bearing for this car, if still installed, would still be going strong. Good luck diagnosing and fixing this issue.

Weazer

DreamCarrera, when I replaced my 1999 Boxster Base's IMS bearing at 72K miles, the original dual row bearing was wobbly on its center stud. I would guess that it had less than 5K miles in it before total failure and the catastrophic consequences for my engine. I had purchased the car with 52K miles, and had religiously changed the oil/filter at 4k mile intervals, and had dissected the filters and never found more than the odd flake or two of metallic material. Just be aware the dual row bearings are wear items and do fail, as the old saying goes, "you can pay me now or pay me later". The only problem with this as that the pay me later part implicates total rebuild of an engine damaged by IMS bearing swarf circulating through all the oil passages and moving parts. Your gamble.