Kalashnikov

Never bothered looking for causes, I am was not paranoid Porsche owner. I got the car with 117k miles, it made that noise when cold. I sold it with 130k+ miles 1.5 years later and it made same noise when cold. It drove fine, never used any oil and based on the acceleration videos was very healthy. I assumed it was a worn lifter as it would tick/knock only when you started the car and engine was cold, it never made the noise when engine was warm.

jumper5836

That how mine started out, it will eventually get louder and start burning oil, sometimes even mine even goes away depending on how it positioned. It likes high rpm and no problem redlining it for ever. I think it's worn in enough that it won't have a problem but I dread idling, I think that will be the killer one day.

Ahsai

Jumper, I remember your case...quite extreme and most experts think your engine won't last that long.

BTW, another good video by Jud (Flat 6 innovation) that can probably help diagnosing whether it's a lifter or scored cylinder.

Ben Z

*delete due to double posting* wtf??

Ben Z

I would agree that a borescope exam would be useful to confirm the diagnosis when symptoms such as oil consumption and/or smoking and/or the sooty tailpipe are present. From what I've read and been told, many if not most times a borescope will reveal some evidence of light scoring in almost all cylinder walls in all engines with many thousands of miles on them. Getting a diagnosis of scoring is not, to me, the same as a diagnosis of engine failure prompting a rebuild. For me there would have to be some additional quantified criteria, such as noise level of the knocking and whether it goes away shortly as the engine warms up and expansion negates the slap or is present always; and amount of oil consumption.

It would be the same if imaging showed me to have cataracts or deterioration in my knees or hips. I would not get surgery unless it was impacting my QOL, so unless I had symptoms that were impacting my QOL, I wouldn't pay to have imaging done.

jumper5836

most cars&coffee crowed been saying that since 2010. That video was from feb 2013 and yet it still is the same.

Ahsai

No one suggested rebuild (definitely I did not). The OP asks what causes the noise and I'm just trying to answer that question. Agree with you. No action needed as long as noise doesn't come back.

And you take that car to Mosport?! Amazing how much you can get out of that engine.

jumper5836

Not since 2012, I bought a 996tt to replace it for track duties. It did get a some great tracking out of it.

Sneaky Pete

I like others want to hope the best but that noise says scored cylinders.

AWDGuy

I had 0 scoring on all cylinders, except 4 & 6. the others looked very healthy.

RRTEC

It very well may be. I plan to scope and get a better look. I have driven 400 miles since adding the seafoam on the off Chance it was a sticking lifter, and the car has been noise free and actually most likely directly tied in with the noise reduction the oil pressure is up to almost 2bar at idle.

I am not overly concerned as the car still runs extremely well, and of course at some point I will have to have been considering rebuilding anyway. In the meantime I will be enjoying the car as is and letting tomorrow worry about itself.

The updates will continue.

alpine003

This is what I call squeezing the most out of a potential bad situation. Drive it till it dies. It may just outlast you or your ownership while still providing some smiles.

You should also note to these guys that some of those 50km involved track miles too IIRC.

jumper5836

Quite a lot of track miles and driving to and from the track.

AWDGuy

same with myself. car ran like a champ, but went through oil faster than gas.

Ben Z

My thinking is, if there was an inexpensive fix for scoring in its early stages that would avert needing to rebuild or exchange the engine, then I would see the urgency to get it scoped ASAP upon hearing the start of cold-idle ticking. (I'm excluding the option of pawning the car off on an unsuspecting buyer). But given there is no other fix, my personal preference would be to drive it until it was smoking embarrassingly and/or using oil excessively. Even a qt of oil every 500 miles is still much cheaper than a new engine. If the car could be driven another 5-10K miles or a year, that would give the person time to save up for a new engine, and put that many fewer miles on the new one.

I remember years ago driving cars tens of thousands of miles with piston slap and using more oil than normal. Maybe that colors my outlook. I do understand the concept of wanting one's Porsche in tip-top condition though. And, the concept of being disgusted that these cars have this kind of issue at such low mileage relatively-speaking for German cars. Our '03 e-class ran 130K miles with zero engine issues, our mechanic said he has customers with over 300K on them likewise, no slap, no measurable oil consumption between changes etc. Honestly had I known these Pcars had such problems (aside from the random odd failure) I would not have bought one, and I won't be buying another.