Air Switching Valve
The ASV is operated by air pump pressure and by intake manifold vacuum through the vacuum switching valve. The ASV redirects air flow from the air pump to either the check valve or to the atmosphere.
When manifold vacuum is applied to pipe 1, the ASV allows air to flow from air pump to the check valve. When the vacuum switching valve directs air pump pressure to pipe 1, the ASV shuts air flow to air injection manifold, and at the same time vents pressure to the atmosphere (air cleaner).