Is there any verifiable gain in disconnecting the throttle body coolant line so that the throttle body doesn't heat up? Seems like a waste to spend $100 on a CAI just so the air can be heated up inside the intake.

Any reasons not to disconnect the line, e.g. icing?

Steve
'95 SE - black!
'00 GLE - white!

 

Coolant passing through the throttle body controls idle speed via the fast idle cam through a thermal sensor. While you may not notice a change in idle when it's hot outside, once it gets cool, you'll find tha your idle won't come down when you're stopped.

 

There is a small plunger type device that moves as the temperature changes and alters the position of the fast idle cam. If you bypass the coolant line going to the throttle body the plunger will remain fixed and the fast idle cam will remain in the position it was last in. If you do this "mod" you should also adjust the idle adjustment screw until your idle is at ~750RMPs. If you've done everything correctly your idle should remain fixed at ~750RMPs and not change with temperature. I've done this mod and felt there was zero gains.