Code : P1491
Make : NISSAN
Description : P1491 NISSAN Vacuum Cut Valve Bypass Valve
Possible causes :
– Vacuum cut valve bypass valve
– Vacuum cut valve
– Bypass hoses for clogging
– EVAP control system pressure sensor and circuit
– EVAP canister vent control valve
– Hose between fuel tank and vacuum cut valve clogged
– Hose between vacuum cut valve and EVAP cani
Solutions :
– Carry out a Reset via CarDiag
– Choose a better quality fuel
– Check that the tank cap is securely closed
– Check the oil level and add more if it is lower than MAX
– Restart an Automatic diagnostic via CarDiag
– If the fault persists, you can check the “Possible causes” listed above : visually inspect (by yourself (tutorials to come) or by a professional) the wiring harness and the associated connectors, check for damaged components, and look for broken, bent, pushed, or corroded connector pins.
