Secondary Air Injection System (EMISSION CONTROL - V8) (page 8 of 8)

EMISSION CONTROL - V8

DESCRIPTION AND OPERATION 17-2-33

Vacuum Reservoir

1 Vacuum port to SAI vacuum solenoid valve
2 Vacuum port to intake manifold 

(one-way valve end)

3 Vacuum reservoir

A vacuum reservoir is included in the vacuum supply line between the intake manifold and the SAI vacuum solenoid 
valve. The vacuum reservoir contains a one-way valve, to stop depression leaking back towards the intake manifold 
side. The reservoir holds a constant vacuum so that the SAI control valves open instantaneously as soon as the SAI 
solenoid valve is energised.

The vacuum reservoir is a plastic canister construction located on a bracket at the LH side of the engine compartment 
on vehicles up to 2003 model year and on the RH side of the engine compartment, near the bulkhead, on vehicles 
from 2003 model year. It is important to ensure the reservoir is fitted in the correct orientation, and the correct vacuum 
hoses are attached to their corresponding ports. The one-way valve end of the vacuum reservoir (cap end, to inlet 
manifold) is fitted towards the rear of the vehicle. 

A small bore nylon hose is used to connect the one-way valve end of the vacuum reservoir to a port on the RH side 
of the inlet manifold. A further  hose connects between the other port on the vacuum reservoir and a port on the front 
of the SAI vacuum solenoid valve.

M17 0212

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