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Scored cylinder failure for your 996, Y or N? tell us (yr, 996 Mk1 or MK2)
I'm curious. Since owning my porsche, I've read and seen a lot more cylinder scoring issues than IMS.
I would like this thread to document the known scored cylinder failures on rennlist. there's tons and tons of theories out there on the cause, but this isn't why I created it, I'm genuinely interested in the numbers of failure, & where the vehicle spent it's time.
me...
2002 3.6, C4S.
discovered scored cylinders at the 106 000km mark (~65k miles)
Canadian Vehicle
Anti case of what you are looking for as there is no sign or symptom of scoring, but still may be of some value.
Just had the top of the cylinders scoped and they came back clean. Without other signs of concern I don't know when we'll drop the pan and look at the bottom of the cylinders.
One owner 2001 C4 6mt with 70k.
Mobile1 for all but the last 2 oil changes (Motul is what the new Indy likes, but I think I'll go back to M1).
Changed the oil mostly based on miles (5-7k). Some had over a year time interval.
Never changed oil weights based on the season.
Never have needed to add oil between changes and the level has never dropped significantly.
Car has always been 100% street parked.
Car has been started and driven in single digit and low triple digit temps.
We have been much better about warming it up in the last few years than for most of it's life.
Saw almost daily usage for it's first 10 years with a good mix of distances and driving conditions.
Last 5 has seen much less usage and what there is typically is barely long enough to warm it up.
She'll get on it from time to time, but she can pull 20+ MPG out of it.
I drive it like we stole it and tend to run it down to a 14MPG average
Much of that may be viewed as apocryphal by some and will give at least one an aneurysm, but it is what it is and it hasn't let us down or given us any significant problems.
The problem is that this somewhat isn't dependent on how old the car is, but if the right person creates the right set of conditions. IMO
Changed the oil in mine after about 5500 miles, mobile 1, old oil looked great and smelled fine, nothing much to get worked up about in the filter, didn't see anything at the bottom of the filter cover, didn't find anything when cleaning up the filter cover, car doesn't use much oil at all.
Just guessing that my cylinders are fine, and even if they weren't I'm not in a $$ position to do anything about it anyway.
AWD, just by reading the research it seems that most engines have these things in common;
Use in colder climates.
Extended oil change service schedule.
Wrong type of oil or wrong oil for their climate.
To protect against bore scoring, you can use an oil more suited for the M96, limit cold weather operation and cold starts w/o a block heater, etc., and do not leave vehicle parked outside exposed to weather, especially cold.
2004 996 C2 Borescoped at 87k miles and no detectable scoring.
Cold climate car. I purchased as CPO in 2007 with 23k miles.
Car originated in Alaska and it has been driven year round during my 8 years of ownership in NE PA.
Oil changes at 5,000 miles using Mobil 1.
Never idled to warm her up. I 'd clean the car off after work and while everyone else did the same with their cars idling they'd often ask why I didn't let it warm up while cleaning it off. Never felt like getting into the explanation of Porsche's recommendation so I'd just say idling cars get 0 MPG.
Having heated seats does help take the chill off though.
I had a Scored Cylinder at 195km in Feb 2014. Had the Motor Rebuilt put about 30km on it already. Likely cause was the Brutal Cold Winter we had in Canada. IMS was like Brand New
I have a MK2 4S. Scored cylinders 4-6, I found out at about 104k KM. It was a DD in Alberta and it was discovered after a borescope was done when a knocking sound appeared in the spring.
It had 5000km oil changes and was stored in a non heated garage. In my circumstance I think the cold was a contributing factor.
Yes 2002 C4S, driven daily up until 2012, winter driven and left outside in freezing every work day in winter.
2008 76k km started a rhythmic ticking and noticed it burning more oil then normal
2010 106k km the tick was louder and burning more oil, used to go through at least 1 liter a track weekend, started blue smoke under cold startup but fine after it's warmed up.
2012 120k km I had it scoped, #4 scored
2016 Now at 136k km ticks loud when cold until warmed up and driven hard, then the tick gets quieter, blue smoke at cold start for about 20 seconds
2018 Now at 137k km. Engine apart #4 #5 #6 scored bad at the top. 1-3 are good.
Last edited by jumper5836; 03-14-2018 at 07:13 PM.
11-20-2015, 11:21 AM
Scored cylinder failure for your 996, Y or N? tell us (yr, 996 Mk1 or MK2)
