Exhaust Manifold: Service and Repair

Removal and Installation

EM-33 Exploded View:

REMOVAL

WARNING:
Perform the work when the exhaust and cooling system have completely cooled down.

NOTE:
When removing bank 1 side parts only, steps 1, 4 and 7 are unnecessary.

1. Drain engine coolant.
2. Remove engine cover with power tool.
3. Remove air cleaner case and air duct (RH and LH).
4. Remove water pipe and water hose.
5. Remove engine undercover with power tool.
6. Remove exhaust front tube and three way catalysts (bank 1 and bank 2).
7. Disconnect steering lower joint at power steering gear assembly side, and release steering lower shaft.
8. Disconnect air fuel ratio sensor (bank 1 and bank 2) harness connectors and remove harness clip.





9. Using the heated oxygen sensor wrench [SST: KV10114400 (J38365)] (C), remove air fuel ratio sensor (bank 1 and bank 2).
A: Bank 2
B: Bank 1

CAUTION:
^ Be careful not to damage air fuel ratio sensor.
^ Discard any air fuel ratio sensor that has been dropped onto a hard surface such as a concrete floor. Replace with a new sensor.

10. Remove exhaust manifold cover (upper) (bank 1 and bank 2).





11. Loosen mounting nuts in the reverse order as shown in the figure to remove exhaust manifold.

NOTE:
Disregard the numerical order No. 7 and 8 in removal.

A: Bank 1
B: Bank 2
<---: Engine front
12. Remove gaskets.

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

INSTALLATION
Note the following, and install in the reverse order of removal.

EXHAUST MANIFOLD GASKET





^ Install exhaust manifold gasket in direction shown in the figure. (Follow the same procedure for both banks.)
A: Bank 1
B: Triangle press
C: Bank 2
<---: Engine front

EXHAUST MANIFOLD
^ If stud bolts were removed, install them and tighten to the torque specified below.
Tightening torque: Refer to "Exploded View".





^ Install exhaust manifold and tighten mounting bolts in numerical order as shown in the figure.
A: Bank 1
B: Bank 2
<---: Engine front

NOTE:
Tighten nuts the No. 1 and 2 in two steps. The numerical order No. 7 and 8 shows the second step.

AIR FUEL RATIO SENSOR

CAUTION:
^ Before installing a new air fuel ratio sensor, clean exhaust system threads using heated oxygen sensor thread cleaner tool (Commercial Service Tool: J-43897-18 or J-43897-12) and apply anti-seize lubricant.
^ Never apply excessive torque to air fuel ratio sensor. Doing so may cause damage to air fuel ratio sensor, resulting in the "MIL" illuminating.

Inspection

INSPECTION AFTER REMOVAL

Surface Distortion





^ Check the surface distortion of the exhaust manifold mating surface with a straightedge (A) and a feeler gauge (B).
Limit: Refer to EM-139, "Exhaust Manifold". Service Limits and General Specifications
^ If it exceeds the limit, replace exhaust manifold.