Why does your 2000 excursion stall when put in reverse?

A 2000 Ford Excursion may stall when put in reverse due to several potential issues. Common causes include a malfunctioning idle air control valve, which regulates engine idle speed, or a vacuum leak that disrupts air-fuel mixture. Additionally, problems with the transmission or electrical system, such as a faulty sensor or low fluid levels, could also lead to stalling. It's advisable to have the vehicle diagnosed by a mechanic to pinpoint the exact issue.