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Old 01-27-2019, 03:07 AM   #21
humfrz
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Quote:
Originally Posted by maslin View Post
Pistons are considerably stronger than valves. When they hit the valve usually just tweaks and will no longer close fully. Worst case the head of the valve breaks off and bounces around in the chamber. Neither issue does anything to the other 3 cylinders.

The vast majority of the time it tweaks the valve just enough to create a decent misfire. Lots of pictures out there of bent valves on other Subaru engines, actual failure rate of the fa20 must be really low.
Interesting comments and speculation.

So, if a valve spring fails and the only negative result is a rough running engine, why in the hell are the manufacturers going to all this trouble and expense for this recall??

Why not just wait till some of the engines just quit running right, then fix just them?


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