Exhaust Manifold and Three Way Catalyst
EXHAUST MANIFOLD AND THREE WAY CATALYST
Removal and Installation
REMOVAL
WARNING: Perform the work when the exhaust and cooling system have completely cooled down.
1. Drain engine coolant.
CAUTION:
^ Perform this step when engine is cold.
^ Do not spill engine coolant on drive belts.
2. Remove engine cover with power tool.
3. Remove air cleaner case and air duct.
4. Remove undercover with power tool.
5. Disconnect harness connector and remove heated oxygen sensor 2 on both banks with heated oxygen sensor wrench [SST].
^ Put marks to identify installation positions of each heated oxygen sensor 2.
CAUTION:
^ Be careful not to damage heated oxygen sensor 2.
^ Discard any heated oxygen sensor 2 which has been dropped from a height of more than 0.5 m (19.7 inch) onto a hard surface such as a concrete floor; replace with a new sensor.
6. Remove exhaust mounting bracket between three way catalyst (right and left bank) and transmission.
7. Remove three way catalyst.
8. Disconnect harness connector and remove air fuel ratio sensor 1 on both banks with heated oxygen sensor wrench [SST].
^ Put marks to identify installation positions of each air fuel ratio sensor 1.
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 inch) onto a hard surface such as a concrete floor; replace with a new sensor.
9. Remove water pipe and heater pipe on both right and left side.
10. Remove exhaust manifold covers (right and left banks).
11. Loosen mounting nuts with power tool in reverse order as shown in the figure to remove exhaust manifold.
NOTE: Disregard the numerical order No. 7 and No. 8 in removal.
12. Remove gaskets.
CAUTION: Cover engine openings to avoid entry of foreign materials.
INSPECTION AFTER REMOVAL
Surface Distortion
^ Check the surface distortion of the exhaust manifold mating surface with straightedge and feeler gauge.
Limit: 0.3 mm (0.012 inch)
^ If it exceeds the limit, replace exhaust manifold.
INSTALLATION
Note the following, and install in the reverse order of removal.
Exhaust Manifold Gasket
^ Install in direction shown below. (Follow same procedure for both banks.)
^ Locate thick side of port connecting part on right side from technician's view.
^ Locate round press in thick side of port connecting part above center level line of port.
Exhaust Manifold
^ If stud bolts were removed, install them and tighten to the specified torque below.
Torque: 14.7 Nm (1.5 kg-m, 11 ft. lbs.)
^ Install exhaust manifold in numerical order as shown in the figure.
NOTE: Tighten nuts No. 1 and No. 2 in two steps. The numerical order No. 7 and No. 8 shows second step.
Heated Oxygen Sensor
^ Install air fuel ratio sensor 1 and heated oxygen sensor 2 in the original position.
^ Install referring the following if the installation positions cannot be identified.
Glass tube color
Air fuel ratio sensor 1*: Black
Heated oxygen sensor 2 (bank 1): White
Heated oxygen sensor 2 (bank 2): White
*: Air fuel ratio sensor 1 are same parts both bank 1 and bank 2.
CAUTION:
^ Before installing a new air fuel ratio sensor and a new heated oxygen sensor, clean exhaust system threads using oxygen sensor thread cleaner (commercial service tool: J-43897-18 or J-43897-12) and apply anti-seize lubricant (commercial service tool).
^ Do not over torque the air fuel ratio sensor 1 and the heated oxygen sensor 2. Doing so may cause damage to the air fuel ratio sensor and heated oxygen sensor 2, resulting in the "MIL" coming on.
Heated Oxygen Sensor 2 (Bank 1) Harness (AWD model)
The section of the harness between heated oxygen sensor 2 (bank 1) and the clamp should be installed tensely due to the secure clearance with front propeller shaft.