Secondary Air Injection System (EMISSION CONTROL - V8) (page 3 of 8)

EMISSION CONTROL - V8

17-2-28 DESCRIPTION AND OPERATION

The air delivery pipe is a flexible plastic type, and is connected to the air pump outlet via a plastic quick-fit connector. 
The other end of the flexible plastic pipe connects to the fixed metal pipework via a short rubber hose.  The part of the 
flexible plastic pipe which is most vulnerable to engine generated heat is protected by heat reflective sleeving.  The 
metal delivery pipe has a fabricated T-piece included where the pressurised air is split for delivery to each exhaust 
manifold via the SAI control valves.

The pipes from the T-piece to each of the SAI control valves are approximately the same length, so that the pressure 
and mass of the air delivered to each bank will be equal. The ends of the pipes are connected to the inlet port of each 
SAI control valve through short rubber hose connections.

The T-piece is mounted at the rear of the engine (by the ignition coils) and features a welded mounting bracket which 
is fixed to the engine by two studs and nuts.

The foam filter in the air intake of the SAI pump provides noise reduction and protects the pump from damage due to 
particulate contamination. In addition, the pump is fitted on rubber mountings to help prevent noise which is generated 
by pump operation from being transmitted through the vehicle body into the passenger compartment.

If the secondary air injection (SAI) pump is found to be malfunctioning, the following fault codes may be stored in the 
ECM diagnostic memory, which can be retrieved using Testbook/T4:

NOTE: Refer to 'SAI System Fault Finding' and 'Checking Malfunctions on SAI System' at the end of this section to 
determine root cause of fault codes.

NOTE: The electrical test of the SAI pump powerstage only indicates that there is a problem with the relay or the 
power supply to the relay. It does not indicate the state of the SAI pump itself (i.e. broken or not connected).

As a result of a SAI pump powerstage malfunction, other fault codes may also become stored in the ECM memory. 
These may include the following P codes.

NOTE: A malfunction of the SAI pump powerstage is logically expected to result in both engine banks reporting the 
same fault.

NOTE: Refer to 'SAI System Fault Finding' and 'Checking Malfunctions on SAI System' at the end of this section to 
determine root cause of fault codes.

Secondary Air Injection (SAI) Pump Relay
The secondary air injection pump relay is located in the engine compartment fusebox. The engine control module 
(ECM) is used to control the operation of the SAI pump via the SAI pump relay. Power to the coil of the relay is supplied 
from the vehicle battery via the main relay and the ground connection to the coil is via the ECM.

Power to the SAI pump relay contacts is via fusible link FL2 which is located in the engine compartment fusebox.

P-code

Description

P0418

Secondary Air Injection System – Relay 'A' circuit malfunction (SAI pump 
powerstage fault, e.g. - SAI pump relay fault or relay not connected / open circuit / 
harness damage).

P-code

Description

P1412

Secondary Air Injection System – Malfunction Bank 1 LH (Insufficient SAI flow 
during passive test)

P1414

Secondary Air Injection System – Low air flow Bank 1 LH (Insufficient SAI flow 

during active test)

P1415

Secondary Air Injection System – Malfunction Bank 2 RH (Insufficient SAI flow 

during passive test)

P1417

Secondary Air Injection System – Low air flow Bank 2 RH (Insufficient SAI flow 

during active test)