Where is expansion valve located on a 2000 grand prix

SOURCE: 2000 pontiac grand prix se ecm location

located in air box beather box for intake.

SOURCE: Where is the AC Low pressure valve on a 1999 Pontiac Grand Prix?

sometimes its behind the alternator real close to the firewall. Find the bigger of the two hoses and pipes the low side is always bigger. Also the cap is blue and the fitting for the charging can will only fit on the right valve.

SOURCE: I need to flush the radiator on my 2004 Pontiac Grand Prix but I

Just take the bottom hose loose and flush away.

SOURCE: Location of mass air flow sensor, 2000 Grand Prix GTP

Hi:
The mass air flow sensor is a round sensor that is mounted in the air intake, between the air cleaner box and the engine throttle body.

SOURCE: code P0442 on a 2000 grand prix

That means that there is a fuel evaporation leak detected in your fuel tank. Generally this means that your fuel cap is loose- go tighten it and see if the code goes away after driving your vehicle for awhile. The problem can also be holes in the evaporation hoses...but not likely.