On the backside of the throttle body/air handler are the 2 vacuum elbow fittings at the top, why is one vented to atmosphere and the other is not ??
Thx
On the backside of the throttle body/air handler are the 2 vacuum elbow fittings at the top, why is one vented to atmosphere and the other is not ??
Thx
Gary
Growing old is inevitable, growing up is optional.......
S.W. Ohio
The one that is not vented is a vacuum reference port (there are actually two of those, one lower on the intake), and the one with small holes in it is the VST Over-flow port (by design it dumps inside and outside, right above the upper throttle blades, in hopes of flooding out the engine should a VST over-flow occur).
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Thanks Don, that makes perfect sense.Originally Posted by EuropeanAM
Gary
Growing old is inevitable, growing up is optional.......
S.W. Ohio
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