Took our 1998 GMC Sonoma to get inspected at they told us to replace our vent solenoid where would that be located Autozone says it is called a purge valve solenoid the garage says that is wrong part we got 3 codes P0446 &P0442 and I can't find the slip for the third one we replaced the gas cap and the one code went away, it failed emissions please help trying to save some money by doing it ourselves

SOURCE: check engine light came on Autozone said needed EVAP purge solenoid?

The problem is, Autozone doesn't use a scanner. They use a scan tool otherwise known as a code reader. I suggest get another opinion at a shop with an actual scanner. They would be more helpful to you. Don't just throw parts at it.

SOURCE: P0440 Evaporative Emission Control

You need a charcoal canister and vent control valve.

You also need the EGR solenoid valve (I think it the brown one).

Valve is located in the valley of the V, towards the transmission side of engine.

Do these 1st and reset light. You may have other issues but you have to start here.

SOURCE: PO 496 emissions code - 2004 Pontiace Grand Am

all the code is saying is taht it the engine is getting outside air from somewhere in the system most probably you miht have damaged the charcoal canister in the bottom of the car the only way to fix this is to replace the charcoal canister

SOURCE: Troubleshooting code: P0442

Here ya go

SOURCE: P0440, P0441, P0446

Error code P0446 is an Evaporative Control System vent control malfunction. DTCs P0441 and P0446 are recorded by the ECM when evaporative emissions leak from the certain components, or when there is a malfunction in either the VSV for EVAP, the VSV for
pressure switching valve, or in the vapor pressure sensor itself.