Cylinder scoring or lifter tick? What to do moving forward?

Hi everyone, My 996 has made this noise twice now over the last few months. Both times after sitting for 2-3 weeks at a time. The first time the oil level was about half on the dash reading, today it was full and had an oil change the last time it was started. Both times the car took a longer period of time to crank over because of a drained battery but it did start up. The noise did go away after driving the car around the neighborhood. I understand these cars do tick but I�m not sure to what extent as I am a first time Porsche owner and was getting potty trained when this car was built. I�ve attached a Reddit url with the video and another post. https://www.reddit.com/r/996/s/GlrKEquWTu

Sounds like a stuck lifter. Scoring would not do that. It might resolve itself over time, but it night need to be replaced in the long run. What oil are you running?

Quotes source post: 19638572

I've had a similar noise when starting up after a long time, or doing a full sump-out oil change. My understanding is it's the hydraulic lifters yapping because they haven't fully filled back up with oil. Especially if it goes away once warmed up - piston slap will do the opposite and become more apparent as the engine warms.

What year is your car? Some of the 5-chain engines are quite noisy when cold, including mine. The tensioners are some of the last devices in the oil supply line to receive oil, so I will start my car and drive off immediately to avoid hearing this disconcerting knocking/rattling when cold. It could also be a loose cat or other exhaust noise. Next cold start - try holding the revs at 2,000 RPM for 10 seconds and see if the noise goes away.

Quotes source post: 19638572

I had a stuck lifter and it sounded a lot louder that this. Also was a lower frequency noise. Yours sounds almost like regular injector tick in the video.

While most 996 ticking issues are indeed bore scoring, this particular one does seem like it could be a lifter, an exhaust leak, loose spark plug, or injector.

Sounds like a weak lifter to me, change the oil to a 15w-50 Driven product and I think the issue will be gone....( at least for a long while) ....

You might try this - https://www.swepcolube.com/products/...-oil-improver/

Quotes source post: 19645451

I have a only-very-hot tick and a low-pressure warning at idle. It only occurs right after stopping after a hard run (uphill). I'm 99.9999% sure it's a lifter, as AC-on silences it. I recently switched to 5w50 Mobil1, but no change. I live in SoCal so pretty much always warmish (some 40-50F mornings). Is 15W too thick for morning starts? I literally just put in the 5W oil 100 miles ago, so like to use that up, but open to trying something after. Is there any concern with running a heavier winter oil if the car is really being pushed hard on every drive? And I hate to open this can-o-worms, but is Driven really a better product than Mobil1? I don't know how to really tell.

Quotes source post: 19645823

I think your car has another issue, I don't think you should ever see oil pressure under .5 bar at idle . Didn't you leave it at an indy?

Quotes source post: 19645844

Yeh i need to post the follow up on that post, gathering some more data. (But yes, it was at indy, but he was focusing on low pressure in turns) Per low idle, I think perhaps with 100k mile engine, and at the temps I've been pushing the car too, it's just going to be low when I come to a stop (I'm seeing more people with similar on here as well).

Quotes source post: 19645823

Consensus is yes. Not that M1 is bad, there are folks with several hundred thousand mile engines that have used M1 exclusively. But Driven is superior.

Yes, Driven has a healthy dose of Moly, that M1 ( or any A40 approved oil doesn't )...Moly is good for protecting the Factory Lokasil cylinders ( or any aluminum parts)... Also I think too many people worry unnecessarily about "cold weather viscosity", and not enough about "hot operating oil viscosity"....I have NEVER seen an engine fail from the oil being too cold, but tons of engines fail from oil being too hot/thin.. Here is the SAE chart for cold weather viscoities ...note that 20w-50 is good down to -20C ( -4F)...so depending on your local temps may be used year round like here in Bama How many people here remember 40-50 years ago using straight 30 or 40 weight year round ? It was never really a problem except on very cold winter days the engine would be slow to turn and start...And if it failed to start people would take an old hubcap and place coal or charcoal in it and sprinkle a little kerosene or lighter fluid on it and light it...then place the hubcap under the engine for 10-15 min to warm it up to start....Even running engines in this type of environment they lasted 90k -100k miles and even then it was the rings and cylinders that had wear.( old grey cast iron..not the newer metals used in modern engines).... the bearings were usually still in fine shape but were replaced anyway... So in my opinion run the thickest most robust quality oil to protect the expensive engine ,and forget about gas mileage and a little pumping losses from the super thin oil.. ( I'm all about longevity in my old age)....

@Porschetech3 do you think DT40 is necessary in Nikasil sleeved engines, like the ones used by LN? I have wondered if these engines benefit at all from the DT40 if the Nikasil is not something that moly will adhere to.

I don't think it is "necessary" on the early 3.4's that have the Ferrostan (iron) piston plating, or the NIkasil plated cyliners, but is on the later engines with Lokasil and Ferroprint ( plastic coating)..... AND is nice additive for other Aluminm parts such as the cam bearing and IMS front bearing , oil pump housing ect... Moly bonds to aluminum, the M96 is mostly aluminum, the factory cylinders ( Lokasil), the cam covers/bearings, the oil pump housing bearing, the IMS beaings.. Zinc and Phosphorus bonds to ferrous metals, crankshaft, camshaft, IM Shaft, Lifters, timing chain and gears, oil pump gears, scavenge pump gears, rings, valves, ect.. The Viscosity Improvers ( Polymers) are synthetic plastic/rubber micro-***** that grow larger with heat, they don't lubricate, just roll around with lubricant on them...They can get " squished" in high pressure areas like between the cam and lifters, but will return to shape like squishing a rubber ball...... but if squished too much they will rupture and the oil will loose viscosity .....This happens moreso on the timing chains/gears and why I advise to change the oil often especially if you are Tracking.......Viscosity Improvers are good, but I like an oil that has a robust base ( not a lot of spread between the cold and hot VI ratings)so it doesn't rely on the VI's or have as many in it...

Quotes source post: 19649877

@Porschetech3 thanks for the reply. I had not given thought to the cam bearings and IMS bearings (in the case of the Solution both are plane bearings). Driven is a premium product at a premium price. I daily the car so oil changes are 2-3x per year. However, my engine investment is many times that so I will swallow the cost of relatively low cost insurance. OP, my lifters occasionally tick on start up on a new build. Ironically, they didn�t do this until I switched from the break in oil to DT40. On the factory engine, if I let the car sit for a week or so, one exhaust lifter would tick on B2. It would go away after a few minutes. When I disassembled the motor I found the bad lifter so replaced it. No bore scoring was found.

Quotes source post: 19649877

Seems to make a lot of sense, this topic brings up some questions for me.... Seems like the crank/rod bearings are the real problem bearings in the m96, Not the m96 aluminum cam bearing or oil pump housing ims bushing/bearing. Looks like the m96 heads get more oil volume/pressure than they need or can return to the sump quickly. m96 cam bearings seem to stay in great shape even when main/rod bearings are trashed from oil starvation. Most all other overhead cam engines show head/cam bearings are the first to wear, being the last in the lubrication circuit to get oil,,, when oil starvation problems crop up. Not so on m96. Maybe those head oil passage restrictor orifices that forum member/racer 'Apex' used in his latest m96 build are the way to go for more oil directed where its needed in a m96.? Seems when the cam bearings only have a problem its most of the time traced back to assembly errors, assembly contamination, or the whole engine is trashed. Not sure I've read of any ims front side bushing problems ever, although I'm sure must be some out there that experienced that. Driven oils are double the cost of other high quality oils that should be more than sufficient for a m96 sleeved nik platted cylinder... no..? jmo

Yeah restricting oil to the top end to allow more flow/pressure to the bottom end has been done on race engines since the 60's ...All competition engines I have ever built used this process, but it needs more discussion as it is not a "one size fits all" recipe.. OEM's don't do this on production engines because they have a wide customer base and don't know who will be owning/maintaining the engines......A dirty owner who lets the oil get nasty will stop up the top end restrictions very early whereas a full flow set up will not stop up early,just wear out slowly... Also installing the top end restricters in an M96 is a very invasive procedure that is best done during a rebuild, not something anyone that owns an M96 would do " just because it's better".... My old saying I've always held to " Dependability is made in the Bottom End and HP is made in the Top End in NA engines" still holds true...... Moly is just a good additive, it is a solid lubricant that is crushed up into a very fine powder and suspended in the oil, it bonds to aluminum but is always there for other parts as well. It is not as capable of extreme high pressure ( flat tappet cams ect..)like Zinc and Phosphorus, but is very helpful in less pressure sensitive areas..So IMHO you need both. I like having the best oil available ..( although difficult sometimes to know which one that is).. I could tell a story where a oil ( a new 20w-50 racing oil) solved a failure problem I was having on camshafts back in the 80's at 12k RPM...It wasn't a lack of oil because it had a spray bar that sprayed a stream of oil directly at each lobe, I had tried several different hardness's of cams and cam followers, different spring tensions ( below 320# the followers would fly off, above 320# the cam would wipe out), nothing could fix the problem, even Crane Cams, Reed Cams, Lunati Cams, Engineers couldn't help with the problem. The new 20W-50 racing oil fixed the problem !! ( MotorCraft Synthetic....MotorCraft was a Sponsor of mine at the time) I ended up setting an IHRA World Record with that engine.. PS :: sorry OP for the thread drift.....

Quotes source post: 19651793

Yes, agree this topic needs more discussion as imo m96 head oil restrictor orifices might be a mandatory mod for the track and engine longevity and maybe for every engine rebuild that will get hard long g's pulled in canyon runs. Or just maybe its for everyone..? I'll start a new thread on it as we'd all benefit from your experience with this as it applies to the m96. The m96 head is a great design no doubt, one of the best. but it does have its valve seat and valve guide issuses that need to be addressed I also know that saying and completely believe in it. The painstaking work I've done on heads most always is repaid 10 fold in performance. Great power and crisp throttle response comes from a perfectly sealing great flowing head, no doubt... You think half a bottle of moly per oil change, dumped in a 15-50 M1 fill would be the same protection for a nik'd engine as Driven...? jmo

Yes I think Top End restricters are a good idea when rebulding an M96, but I look for improvements/developments that will help the vast majority of 996 owners that are out there.( like UAOS/UIDS ect)....Most owners will not want to install restricters unless they are doing a rebuild, it is just too invasive but there is no downside when done properly. First rule in modification/developing/re-engineering is to do no harm... When I think of oil for an M96 I look for the most robust viscosity first, then I want very good resistance to aeration ( PAO+Ester), then I want healthy doses of Moly+ Zinc+ Phosphorus, I don't really care about the additives that clean or make the oil last longer as I change the oil when needed and don't care how often that is.... I have a lot of experience with engines and common sense but I am not an expert chemist/Tribologist so I listen to them also....but no one ever proves what is the "Best" oil available..If I had unlimited R&D $$$ funds I would take a handfull of rock-stock BRZ's ( also known for oiling issues) on the hottest day of the year and put them on the Track and test the top suspected oils to engine failure to see which one performed best ...lol......The big oil companies probably know who has the best, or maybe they are all so close they wouldn't call it...but they never do published head-to-head tests........that's why "oil threads" are the most debated and **** stirring of all....