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Catalytic Converter: Service and Repair




EXHAUST MANIFOLD AND THREE WAY CATALYST

Removal and Installation












REMOVAL

1.Disconnect battery negative terminal. Removal And Installation Coupe (Coupe models) or Removal And Installation Sedan (Sedan models).
2.Remove the engine undercover.
3.Remove front RH wheel and tire. Adjustment.
4.Remove fender protector side cover RH. Coupe (Coupe models) or
Sedan (Sedan models).
5.Remove generator. Service and Repair.
6.Disconnect the electrical connector of air fuel ratio (A/F) sensor 1, and unhook the harness from the bracket and middle clamp on the cover.
7.Remove the air fuel ratio (A/F) sensor 1 using Tools.






CAUTION:
- Be careful not to damage air fuel ratio (A/F) sensor.
- Discard any air fuel ratio (A/F) sensor 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.
8.Remove the exhaust manifold cover (lower).
9.Remove the exhaust front tube. Removal And Installation.
10.Remove the exhaust manifold cover (upper).
11.Remove the exhaust manifold stay.





12.Loosen the nuts in the reverse order as shown, on the exhaust manifold and three way catalyst assembly.
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13.Remove the exhaust manifold and three way catalyst assembly and gasket. Discard the gasket.

INSPECTION AFTER REMOVAL

Surface Distortion





- Use a reliable straightedge and feeler gauge to check the flatness of exhaust manifold fitting surface.
Limit: 0.3 mm (0.012 in)

INSTALLATION

Installation is in the reverse order of removal.





Tightening Exhaust Manifold Nuts
- Tighten the nuts to specification in the numerical order shown, on the exhaust manifold and three way catalyst assembly.
Installation of Air Fuel Ratio (A/F) Sensor 1
Clean the air fuel ratio (A/F) sensor 1 threads with the suitable tool, then apply the anti-seize lubricant to the threads before installing the air fuel ratio (A/F) sensor 1.

Oxygen sensor thread cleaner: J-43897 - 18
Oxygen sensor thread cleaner: J-43897 - 12

CAUTION:
Do not over-tighten the air fuel ratio (A/F) sensor 1. Doing so may cause damage to the air fuel ratio (A/
F) sensor 1, resulting in a malfunction and the MIL coming on.
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