would a gas cap cause po446 97 gmc jimmy

Question

could a gas cap cause this code po446

Answer 1

P0446 EVAP canister vent blocked

Yes the fuel cap can cause this code, but it more of a evap vent valve.  The real culprit with this code is the FTP (fuel tank pressure) sensor, When the fuel tank pressure sensor sends the wrong pressure signal you code up P0446 a replacement of the FTP is the solution . The location is on the fuel pump module