Why does your S-10 stay on high idle after starting?

If your S-10 remains on high idle after starting, it could be due to a malfunctioning idle air control (IAC) valve, which regulates engine idle speed. A vacuum leak can also cause an elevated idle by allowing extra air into the intake manifold. Additionally, issues with the throttle position sensor (TPS) or a cold engine in cooler temperatures can lead to higher idle speeds. It’s advisable to have these components checked for proper function.