Anti-Backfire Valve

The anti-backfire valve is used to prevent backfire in the exhaust system during deceleration on 210 models only. At the start of deceleration, the air/fuel mixture in the intake manifold becomes too rich to ignite and bum in the combustion chamber. The anti-backfire valve provides additional air to the intake manifold to make the air/fuel mixture leaner and prevent backfire. If the valve is faulty, unburned air/fuel mixture will be emitted to the exhaust manifold and ignite when mixed with secondary air, causing backfire.

Fig 1: Air Induction Systems (Typical)

Courtesy of NISSAN NORTH AMERICA, INC.

Fig 2: Air Induction System Components

Courtesy of NISSAN NORTH AMERICA, INC.

Fig 3: Anti-Backfire Valve (210 Models Only)

Courtesy of NISSAN NORTH AMERICA, INC.