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YOUR RESEARCHThoughts on this engine sound?
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Check #5 and #6 through the spark plug holes
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Suggestion
If you want the quick test, then check #5 and #6 through the spark plug holes.
Leading evidence: 'Check #5 and #6 through the spark plug holes' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check #5 and #6 through the spark plug holes' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Suggestion · Original poster
I already need to change my plugs and coils, so checking that way is killing two birds with one stone.
Replace plugs and coils so i'll be doing a borescope
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Suggestion · Original poster
I need to change my plugs and coils so I'll be doing a borescope that way to start.
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Suggestion
But you could also use Mechanic Ears to listen for the ticking sound.
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2003 C4S with 140k
I understand bore scoring is a common issue, but my car doesn’t have any (significantly) noticeable oil consumption or blue smoke.
Maybe I’m overthinking and should get used to normal Porsche ownership. Sound clips online aren’t very easy to compare. Hoping some other owners can chime in.
This video is taken from the left side bank.
You Tube
You Tube
Thanks!
I have been through bore scoring and had Jake Raby rebuild my engine and that is my only qualifications. I don't hear much to worry about on your car. Sounds like just valve train noise to me.The best way to hear the tap-tap-tap indicative of bore scoring is to put the phone on the ground beneath the headers and leave it for 15-20 seconds without waving it around. I thought I heard something but not sure. Put it on the ground and record post back here.
Yeah, I don't know...inconclusive for me. Keep an eye and ear on it. Also seeing actual blue smoke is not common for bore scoring. Sooty exhaust tips are as well as "spitting" on a cold start. Chart your oil levels for usage. Measure with the stick with car on flat ground before first start of the day(overnight/cold engine). Do not overfill. My guy recommends keeping oil level at 1/2 stick and only adding oil when at the low mark and only enough to bring it back to 1/2 stick. How many miles on your car? Do you know how long the injectors have been in the engine? Do you know the history of ownership, specifically locations?
I can tell you when I bought my car in 2014 all the engine noise coming from the back drove me crazy. Last rear engine car I had was a 1964 VW bug in 1969 so that was a while ago.
Keep us updated.
BTW Welcome to the forum.
The car has 88k miles and has spent its time in Chicago and Ontario; we think the car was never winter driven as indicated by the lack of any corrosion and no sign of salt on interior carpets. I bought the car with a limited service history but had a reputable Porsche indy complete a PPI and I got the all-clear. I have an upcoming major service to change plugs, coils, and fix 2nd gear synchro (covered by my extended warranty). When I had my oil changed last year the mechanics did a visual inspection of the filter and didn't notice anything ferrous.
I don't have (noticeably) sooty tips and on cold starts I have mild "spitting", but it seems to be condensation with the very odd bit of black carbon. What's wrong with a little spitting?
My Spidey Senses were tingling and I thought it's best to share my journey. Happy to have my first post in the books - looking forward to fun trips in the car!
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I could spot that 100 yards away... Even with partially damaged hearing from jet engines, and dynos.
Any noise like this must see a bore scope from the sump, and spark plug hole to verify the issue is NOT bore scoring before any money is spent on something that is believed to be noisy lifters.
Lifters that are noisy comes from excess lash, and the lifters in these engines do not fail in that manner. You may have an oil delivery issue that is reducing the flow of oil to the hydraulic lifters, thus adding lash to them. That can make for noisy lifters, and a broken oil pressure relief spring is usually the culprit.
In every case where I have found noisy lifters, I was able to confirm these were the issue due to interruptions in the exhaust note/ pulses that coincided with the rhythm of the noise. Pressure transducers c an be used to plot this, and compare it to the firing sequence of cylinders to pinpoint it.
In short, you never assume that a "lifter noise" is a lifter noise with these engines. You can easily waste thousands of dollars with this approach. Assume nothing. Quantify everything. That starts with a visual bore scope inspection to rule out scoring, and it must be done from both sides of the cylinder- not just one "because that's easy". If done from one side,(spark plug hole) you see 50% of the picture, and miss the most critical area where scoring begins.
Seemingly simple question, but what�s the best way to spin it after I�ve dropped the pan and pulled the plugs? Going to get more serious about assessing the real condition of this when it warms up. 2003 tiptronic. This is to scope both sides.
Wow this is all great, hoping the outcome is as good as the advice.
I will start by looking at each of the plugs for oil residue and differences in combustion patterns. I will then do a bore scope from the spark plug -- going from the sump is a little difficult for a garage job. I haven't noticed my oil pressure gauge act out of the ordinary.
End of the day, I know that these engines are all prone to scoring, it's a fate of their existence. Nonetheless, I hope I don't have a bigger problem than anticipated.
A water pump bearing that has failed can cause a rattling sound - easy enough to check by taking off the serpentine belt and seeing if there's any wobble in the pulley. Lots of good advice above on things to investigate. Good luck
Pull the sump and look at the crank side of the cylinders....otherwise you will be primarily guessing. It's not hard to do at all, in fact I pulled my whole engine/transmission out of the car while it was on jack stands.
Let me know if you want to see some bore score pics....2004 C4S with 84,000 miles.
I need to change my plugs and coils so I'll be doing a borescope that way to start. Pulling the sump is a little labor intensive and I want to get a general idea of the amount of scoring. If it's substantially then I'm sure it will be noticeable through the plugs.
Just remember, scoring starts at BDC on each cylinder. If you want the quick test, then check #5 and #6 through the spark plug holes. But you could also use Mechanic Ears to listen for the ticking sound.
I'm beginning to wonder whether it's just easier to do the sump during an oil change. I've been at it for off and on two days, removing mufflers and brackets to look with the scope. I think when I pull the sump it'll be easier to look at the back side.
I do understand where you�re coming from. I already need to change my plugs and coils, so checking that way is killing two birds with one stone. Dropping the sump plate may be easier if I had a lift, and my Indy wants CAD600, which I think is a little much.
If I notice substantial scoring at the top of the cylinder then I know I have a more serious problem on my hands. Whereas if there�s minimal (or no) scoring, then I don�t need to be as worried.
Also I don�t really hear any ticking on the passenger side of the car so I�m not inclined to believe it�s the typical #5/6 scoring.
Just wrapped up doing photos of all six with the mufflers and bumper pulled on jack stands and I don�t see pulling the sump as a problem the way it is at the moment. Sure, look at the top like I just did while you�re in doing plugs and coils. It was good practice learning how to move the stethoscope cam around. Actually looking forward to seeing what�s there or not in the sump.
So I couldn�t wait for the parts or the borescope so I went ahead and pulled #6. I know I know, I should wait and do my borescope, but I�ve been impatient. Let me know what you guys think, looks not bad to me. No oil on the threads, ignition pattern looks decent, but there seems to be a little bit of oil on the washer.
Not perfect, but not terrible!
