At 08:28 PM 3/6/2001, Larry Alofs wrote:
>I'm having some trouble accepting the idea that in the part of the exhaust
>system that is presumably under some pressure, a leak would cause air to
>come in.
>   Could someone explain this?

The exhaust comes in pulses as each exhaust valve opens -- the moving gas
has inertia and creates a little vacuum in the pipe after the exhaust valve
closes.  The system can also form an acoustical oscillator, which will make
the effect even more pronounced.

david

David Beierl - Providence, RI
  http://pws.prserv.net/synergy/Vanagon/
'84 Westy "Dutiful Passage"
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