1994 S-10 2.2 revs races high at idle. What could cause this?

A 1994 S-10 2.2 revving high at idle could be caused by several factors. Common issues include a vacuum leak, which allows extra air into the intake, or a malfunctioning idle air control (IAC) valve that fails to regulate engine airflow properly. Additionally, a stuck throttle plate or a faulty throttle position sensor (TPS) could also lead to high idle RPMs. It's advisable to check these components to diagnose and resolve the issue.