PeterC4

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?

jumper5836

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.

Cosmo Kramer

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.

ivangene

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

jumper5836

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

ivangene

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

Cosmo Kramer

Wow that's noisy! I would say that cylinder is scored and oval causing piston skirt slap. Or it has a scored cylinder and a bad rod bearing.

soverystout

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.

jumper5836

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.

PeterC4

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.

alpine003

Was this a track driven car?

KrazyK

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.

soverystout

Damn. that certainly adds to your cost of ownership..... Jeeze.....

KrazyK

Was it burning a lot of oil? I know they claim 1 qt per 1K miles is normal but that is total BS.

jumper5836

Oh ya, it has lots of track mileage.