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No compression in #3 cylinder

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THe car is a 2003 Boxster S No mods, 46k mi.

My wife was driving on Hwy 99 and the car just started running crappy,OBD slight came on, car told her to

take to service (cute little comment).

Drove out to check out car and yep it was really running crappy, very rough.

Had it towed to independent Porsche repair shop.

They are trouble shooting it right now, completing compression check.

#3 spark plug was fouled, they checked the oil/air separator, no compression in #3 cylinder.

outlook is? Poor right?

Ideas, opinions, BTDT's

Pisser is we have only had the car for about 2 months/1k mi.


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Check the timing and see if that bank is off.

Also check to see if there is any valve strike marks on the #3 piston via boroscope.

Metal in the filter?

could be a broken valve spring -- this would be relatively cheap, esp if the valve didn't get stuck far enough

open to hit anything -- but was still open enough to loose compression.

good luck with it.


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If the timing were off on that bank, then the other three cylinders would have similar compression problems.

They need to dump the oil and take a close look to see if there is oil-coolant mix from a cracked cylinder liner. Usually these don't happen with the cylinders on the end (only on the middle ones), but the oil should be checked regardless.


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