Posts Tagged: idle speed

What is an idle air control valve and how does it work

Learn how an idle air control valve works An idle air control valve bypasses air around a closed throttle plate so the engine can get air at idle. Because it bypasses air, it’s also called an air bypass valve. Back in the days of carburetors, idle speed was adjusted by way of an idle speed screw that forced the throttle plates open by a crack. In fact, on many carburetors, there were two idle speed adjustment screws; one for hot idle and another for cold. Turning the screw inwards prevented … Read More