Component description of aspirator shutoff valve with integral check valve - GF14.30-P-2100SM

ENGINE 113.986

ENGINE 113.987

ENGINE 113.988

ENGINE 113.989

Fig 1: Identifying Left And Right Aspirator Shutoff Valves - Engine 113.988

For each cylinder head, an aspirator shutoff valve with integral check valve is located at the front of the engine.

Task

When air pump is switched off, the aspirator shutoff valves prevent air being inducted into the exhaust ports, as a result of the flow of the exhaust gases.

Function

Fig 2: Aspirator Shutoff Valve Function Diagram - Engine 113.988

The aspirator shutoff valves are opened via the air pump switchover valve (Y32) through vacuum or closed through ventilation. The injected air to the electrical air pump (M33) can thus flow through when the aspirator shutoff valves are actuated.

When air injection is off, the check valve prevents the admission of exhaust gas in the vacuum diaphragm and thus protects these from dirt and thermal destruction.