What would cause egine to rev up or stall when ideling when egine is hot?

When an engine revs up or stalls while idling when hot, it could be due to several issues. A common cause is a vacuum leak, which can disrupt the air-fuel mixture. Additionally, a failing idle air control valve or throttle position sensor can lead to improper engine management. Lastly, overheating components like the fuel pump can also affect engine performance during idling.