How to replace mass air flow sensor Chevy 1999 Astro van?

The MAF sensor is between the air filter housing and the throttle body. The removal should be straightforward with simple hand tools. Handle the new sensor with care, and be sure to place a small amount of dielectric grease on the connector for the wiring harness. Be sure to carefully reassemble the connections from the throttle body to the MAF, and on to the filter housing, as any air leaks will cause drivability issues and could allow dirt to enter the engine.