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      07-24-2014, 02:00 PM   #257
anom3
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Drives: F30 335ix
Join Date: Apr 2014
Location: Behind the wheel

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i dont think so.

i have 'looked' at the sound a few times, and there is actually a succession of multiple knocks in a row. most recordings i have 'looked' at had 6-8 very quickly one after another.

plus, my secondary air pump is disabled via tune (noise was there before the tune went in btw).

have a look at this, this does not sound like a valve opening:



Quote:
Originally Posted by lsmkr01 View Post
That clank sound is the valve opening to allow the secondary air pump flow through the exhaust during cold start.
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