Anyone know exactly what the bypass valve on the intake manifold does? I don't mean the AEM one that prevents water from being sucked up. This valve is located on the stock intake manifold not air intake pipe of 1995 B18C1.

 

Could you be more specific? PCV Valve?

 

its generally for looks. i have read in many instances that its not good for your motor. because it does not suck air, air is moving freely back and forth, to help vent the valve cover. i dont remember the specifics on why it is bad. i have one, reason being, my intake does not have the hole for it.

 

It's not the PCV valve, and to be more specific, it's actuated by vacuum via a solenioid. There is a 2 prong connector beneath the intake manifold that connects to the solenoid that controls it. It looks like it has a flap inside the intake manifold. I have checked with the Acura dealer's parts counter; when referenced it's called a bypass valve.

 

Sounds like the IAB (intake air bypass) or whatever its called. GSR intake manifolds have both long (for low rpm) & short (high rpm) runners. There's little butterfly valves (like throttles) in the short runners. These open up at some speed.

There's a vacuum motor & a bellcrank over on the side near the alternator. That opens & closes them.

 

Sounds like an accurate description of it. It's on the driver's side of the intake. I'm missing the solenoid that controls it; need to find one. I've emailed some ppl that have parts for sale, nothing yet. I'm gonna try the junkyard as well.

Thanks for your reply on this one.

"If you send something by truck, why is it called 'shipping'?"