Background info: The air cleaner is equipped with two inlets, one of which is opened or closed by the Intake Air Control (IAC) valve #3. This system reduces intake noise. When the engine is operating at low to mid speeds, this system operates the IAC valve to close one of the two air inlets. When the engine speed is more than 3,200 rpm and the opening angle of the throttle valve is more than 30 degrees, the ECM activates the Vacuum Switch Valve (VSV) and opens the IAC valve #3.

We will re-route the vacuum hoses so that you bypass the VSV and connect IAC valve #3 (a.k.a., the "flapper valve") to a constant vacuum source. This will keep IAC #3 always fully open at all engine speeds resulting in less air flow restriction, decreased throttle lag and some improved low-end performance.

This is a photo to orient you as to where you'll be working (the parts in question are in the yellow circle).

Here's a close-up view. Disconnect the two vacuum hoses at the points as indicated in the yellow circles.

Now reconnect the vacuum hose going to IAC valve #3 to the open port on the "T" connector. That's it you're done!

If you want to get fancy, you can buy about a 5" long piece of 5/32" (I.D.) vacuum hose and two 5/32" vacuum plugs (caps). Connect one end to IAC valve #3 and the other to the "T" connector, then plug the 2 open ports on the VSV to keep any dust or dirt out. Keep the two pieces of stock vacuum hose in your car in case you want to reverse this mod before you bring your car back to the dealer for service, etc.