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YOUR RESEARCH996 Engine Problem - Tapping Noise - Engine Swap Required?
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Replace engine due
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996 Engine Problem - Tapping Noise - Engine Swap Required?
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Leading evidence: 'Replace engine due' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check tomorrow' (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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Performed · outcome unconfirmed
Other symptoms are the catalytic converters needing to be replaced every 1.5 years but the car has been burning through cats since I got it in 2003.
996 Engine Problem - Tapping Noise - Engine Swap Required?
Replace first 8 years they
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For first 8 years they were replaced under warranty.
996 Engine Problem - Tapping Noise - Engine Swap Required?
Run r compounds though
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996 Engine Problem - Tapping Noise - Engine Swap Required?
Check tomorrow
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996 Engine Problem - Tapping Noise - Engine Swap Required?
Run horrible he had
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Suggestion
It never burnt any oil, we went to a track day, he got the engine light warning and the engine was shaking and running horrible he had to flat bed it to dealer.
996 Engine Problem - Tapping Noise - Engine Swap Required?
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I have a 2004 996 with 83K that runs well. A tapping noise has become more pronounced of late to I went to the dealer for a diagnosis. It appears that one of the cylinders is scored and a swap for a rebuilt engine is required. For some reason the car was also low on coolant last month. I will get a second opinion, but here in Canada it's going to be a $28k cost. Any alternatives?
There are a few indy's that can rebuild the engine for about 13k. Rebuild and upgrade to a 3.8l for 18k.
Find a used engine from a salvage car that got front/side impact damage and written off.
Take you chances on a ebay rebuilt engine.
I have a hard time believing that a scored cylinder is causing a tapping noise. Any other issues other then the noise (ie. exhaust smoke, poor idle, misfiring)? Did the shop do a leakdown and get poor results on that cylinder? If that is the case, get the cylinder wall inspected with a boroscope.
You could just have carbon buildup under one of the valves. This would cause poor leakdown results and increased valve lash, which produces a tapping sound. As for the coolant loss that could be anything in the system. Get the cooling system pressure tested and find out where it is leaking.
yea...you have to get a second opinion....
scored cylinder? - never heard that one
stuck lifter
cracked lifter cradle
broken valve spring
these sound more likely
did they bore scope the suspect cylinder?
(because I have seen one that had something impailed into the top of the head...that until broken down we will not know what it is, but suspect part of a ring?)
time for a second opinion, or some bore scope pics
That is funny, scored cylinder is more common then IMS.
This is interesting reading about it.
part 4 and part 5
http://www.hartech.org/buyers.html
I have one and it taps. Spark plugs pulled and borescoped to find that #4 is scored.
Here is my engine noise, noisy at 1100 rpm. RPM range in the Video is from 800-2000
HMMM...I seriously have not paid that much attention to that - but will keep my eyes, and ears out for it - I agree with your comments about the 3 letter acronym - but it is something that can be fixed in the cars - and doesnt cost much - worn cylinders - not so much.....
thanks for the video reference
My bet would be on a stuck lifter making that noise. The scored cylinder amy cause somewhat lower compression #s on that cylinder but may not be the issue related to the noise. Especially if the engine runs strong.
Engine does run strong. Though I have high oil consumption and blue smoke when engine is cold at first start up when weather is also cold. Hot days or on cold days with engine warmed up, no blue smoke.
Other symptoms are the catalytic converters needing to be replaced every 1.5 years but the car has been burning through cats since I got it in 2003.
I went to the dealer this morning and spoke to the tech. He was very knowledgeable and they did inspect the cylinder wall with a boroscope. It is badly scored from the picture I saw. As a result the piston taps against the wall as it goes up and down and it will get worse with time. Since there are no "sleves" in the cylinders for this version of engine, the clynder bore is part of the engine core, so your options outside of re-boring the engine are limited. I spend time with the the tech, the head of service, my service rep and my wife and I reviewed all of the options. A remanufactured engine is basically new that comes from Porsche, but I am looking for some warranty relief and othe concessions to allieviate the cost. I understand all of the parts on the engines from Porsche are new and there is a 2 year warranty. There are some other options too, but without a viable engine, the car is not worth much right now.
I have been reading more and more about scored cylinders lately. It seems to be another issue with the 3.6L. Just add it to the list of failures I guess.
Interestingly, my car was not a track driven car (a few times only). My wife used it as her daily driver. I was driving it more frequently when we first got it, but for the last few years she has been driving it and that may contribute to the problem as she tends to drive shorter distances. My car never started buring oil until the tapping started and I could see from the removed plug the tech showed me on the damaged cylinder it was very dirty. I believe that there have more instances of this type of problem and the tech told me that for some reason it is in the 5th and 6th cylinders with more frequency. I am waiting to hear from Porsche on the cost.
Correct, the damaged cylinder is not repairable. I have a good relationship with the dealer and will be dealing with Porsche Canada directly myself as well. It's about a new/replacement engine.
Another cold weather driver? Anyway, this is not an isolated incident. If the "tapping" noise is pronounced, take it to the dealer right away and find out what the problem is.
About oil consumption, I have to say that my car does not need any oil topping at all. I change the oil pretty often but even after a track day, the oil level is the exact same.
I think the cylinder bore problem explains well with the high oil consumption.
I can't believe the noise is so loud though, just because of a scratch on the cylinder bore. strange.
Very interesting discussion on the scored cylinder topic. How difficult is it to boroscope the engine and what is the process entail? What is the "ultimate outcome" if not addressed? Seized engine? Engine grenade? Other?
Take out the spark plugs and rotate the crank for each cylinder. Now a days you can buy a boroscope at Home Depot and such. Hell, even Harbor Freight carries a decent one for the casual user. Best if you can get one with a camera built in with USB or SD card so you can blow it up on a bigger monitor.
A friend on the forum with a similar 04 C4S. Replaced his engine due to the same problem. It never burnt any oil, we went to a track day, he got the engine light warning and the engine was shaking and running horrible he had to flat bed it to dealer.
Just saying oil burning may show signs but you may have no signs and it may score the cylinder in a brief moment. In my case my engine still lives and even has many more track days but in my friends case it was to bad to even run.
I have had the X51 pan before starting to use R compounds and my local track (Mosport) which is not very hard for g-force corners and doesn't have steep banking. It does though have a fairly steep hill but it is very short in corner 5.
G forces are not the root of the issue. They are only one portion of a chain of events that we call "The snowball effect". I have 17 cars on site now that are here because of it.
We currently have cars here from 23 states. Of these 17 of them are here due to circumstances related to the issue that has been discussed above.
Oh, make that 22 states, one just left to get loaded on a truck back to Wisconsin with a fresh big bore engine installed. It also had the "snowball effect" land it here.
Not limited to cylinder issues, mostly lost main and rod bearings. The bulk of what we have here now is due to a loss of viscosity and the lack of film strength resulting from that. This changes over time and comes in spurts, a few months ago the issues were mostly intermixed coolant and oil, then a rash of IMSB failures, then bad timing chains. It constantly changes and we are constantly slammed.
I'm new to this site.I like reading and learning about different engines.
Dosen't the 3.6L engine have liners/sleeves and are Nikasil coated?,and if dosen't
have liners why can't you have an engine builder send the motor out for repairs?
I am very surprised that at 80k you are having problems.
On my Factory 1991 corvette LT5 DOHC engine came with liners that are Nikasil coated,and there are few ZR-1's with A couple hundred thousand miles on them with no issue's.
I would think that the factory would have some sort of warranty against manufacturing defect.
AL.
The liners end up being an integral part of the block.
They are not replaceable in the usual sense.
Some engine shops machine away the cylinders entirely and fit new cylinders. These are secured at both their base and at the top.
'course, this is a very expensive operation. The engine has to be removed, stripped down and the block halves separated, machined, the engine reassembled, tested, and installed and tested again.
This is a source reference. Confirm exact model applicability in the original material.
