Deceleration Valve
- Remove air cleaner, plug air cleaner vacuum source and connect tachometer to engine. With engine running at idle, remove deceleration valve signal hose from intake manifold.
- Reconnect signal hose while listening for airflow through ventilation pipe and into deceleration valve. Engine speed should drop when hose is reconnected.
- If airflow lasts less than one second or engine speed does not drop, check for defective hoses or deceleration valve.