Exhaust Manifold and Three Way Catalyst: Removal and Installation

Exhaust Manifold and Three Way Catalyst: Removal and Installation [QR25DE]

REMOVAL
1) Release fuel pressure.
2) Remove quick connector cap, and disconnect quick connector at the engine side.





3) Remove air duct, PCV hose (between air duct and rocker cover) and electric throttle control actuator.
4) Disconnect harness connector of air fuel ratio sensor 1, and harness from bracket and middle clamp.
5) Remove air fuel ratio sensor 1 using Tool.
Tool number: - (J-44626)

CAUTION:
^ Be careful not to damage air fuel ratio sensor 1.
^ Discard any air fuel ratio sensor 1 which has been dropped from a height of more than 0.5 m (19.7 in) onto a hard surface such as a concrete floor; replace with a new one.

6) Remove exhaust front tube.
7) Remove exhaust manifold cover.
8) Remove bracket between exhaust manifold-three way catalyst assembly and transmission assembly.
9) Loosen nuts in reverse order as shown to remove exhaust manifold and three way catalyst assembly.





10) Remove gasket.

CAUTION:
Cover engine openings to avoid entry of foreign materials.

INSPECTION AFTER REMOVAL

Surface Distortion
^ Check the surface distortion of exhaust manifold and three way catalyst assembly mating surface with straightedge and feeler gauge.





Limit: 0.3 mm (0.012 in)

^ If it exceeds the limit, replace exhaust manifold and three way catalyst assembly.

INSTALLATION
Installation is in the reverse order of removal.

Exhaust Manifold
1) If stud bolts were removed, install them and tighten to the specified torque.
Exhaust manifold stud bolt: 14.7 Nm (1.5 kg-m, 11 ft-lb)
2) Tighten nuts in numerical order as shown.





3) Tighten nuts in numerical order as shown again.

Air Fuel Ratio Sensor 1

CAUTION:
^ Do not over tighten air fuel ratio sensor 1. Doing so may cause damage to air fuel ratio sensor 1, resulting in the "MIL" coming on.
^ Before installing new air fuel ratio sensor 1, clean exhaust system threads using a heated oxygen sensor thread cleaner and apply anti-seize lubricant.

Tool number
: - (J-43897-12)
: - (J-43897-18)