1998 Chevy Silverado Didnt pass smog. P0430 code

Engine Performance problem
1998 Chevy Silverado V8 Four Wheel Drive Automatic

Thank you for your response. It helped id the part that the hose was missing from. The part was #1 in the emission hose routing diagram. The hose that was missing is not shown in the picture. On my eng, the switch or solenoid has a place for a hose on the left side of the switch. I cant find where this hose connects. Once again THANKYOU for your help JOE B