Reliant L4-156 2.6L SOHC (1984)
Pulse Air Feeder: Description and Operation
Fig. 31 Pulse air feeder (PAF) system. 4-156/2.6L engine
This system, Fig. 31, is used on 4-156/2.6L (2.6 liter) engines. It supplies secondary air into the exhaust system between the front and rear catalytic
converters in order to promote the oxidation of exhaust emissions in the rear catalytic converter.
The PAF consists of a main reed valve and sub-reed valve.
The main reed valve is actuated in response to movement of a diaphragm which is activated by pressure pulsation generated by the reciprocating
motion of the number 3 piston. The number 3 cylinder crankcase is sealed by a seal cover which has a small hole for discharging engine oil and blow by
gases.
The sub-reed valve is actuated by exhaust vacuum generated from pulsation in the exhaust system between the front and rear catalytic converters.