Just trying to figure out how the ISC assembly works for future reference. From my manual, I see it has a hose to the intake silencer, a hose to each throttle body, and a vacuum hose with filter to the intake manifold. I assume the valve itself opens and closes as needed and allows air flow from the intake manifold into the throttle bodies. I believe the hoses to the throttle bodies provide a vacuum to suck the air in as needed from the intake silencer connection with the valve electronically contolled to "throttle" the air flow. What does the vacuum line from the intake manifold do? Am I way off base here? Also, I have read some posts about cleaning carbon buildup from the ISC assembly to fix idle problems. Where does that carbon come from? Maybe the breather pipe hooked from the valve cover to the intake silencer? The more I understand the less silly questions I will pose later. Thanks in advance.
