where is the the EVAP vent valve located in the 2001 Chevy Blazer located

Question

vehicle's 4wd light stays on says check .. not shifting gear to drive, code P0440 is indicated , need to know what this means and where the problem located

Answer 1

P0440 Evaporative emission control system malfunction

The vent valve is under the spare tire well, you will need to remove the spare tire to access it. This valve has nothing to do with the not shifting into a drive gear, Beside P0440 see if there is another code with the 4x4 or the transmission