Exhaust in Solenoids

[headlight]

A single solenoid should be enough to control both the A and B ports. The important thing is that it is a 4/5 port solenoid.

If there is air leaking out of the exhaust port it is usually either an internal leak in the seal of the air cylinder or a leak in the gasket between the solenoid and the manifold block (if you are using a manifold setup).