Installation [10/2022 - 08/2023]: Procedure

WARNING: This page is about a different car, the 2025 Lexus RX 450h+, 2025 Lexus RX 350h, 2024 Lexus RX 450h+, 2024 Lexus RX 350h, and 2023 Lexus RX 350h. However, it is still accessible from the selected car via links, so may be relevant.

INSTALL NO. 2 EXHAUST MANIFOLD HEAT INSULATOR
Torque: 11 N.m (112 kgf/cm, 8 ft.lbf)
INSTALL EXHAUST MANIFOLD TO HEAD GASKET

INSTALL EXHAUST MANIFOLD (TWC: Front Catalyst)

Fig 1: Exhaust Manifold (TWC Front Catalyst) Bolts Tightening Sequence

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*1	Exhaust Manifold (TWC: Front Catalyst)	*2	No. 1 Exhaust Manifold Heat Insulator
*3	No. 1 Front Floor Heat Insulator	-	-

Temporarily install the exhaust manifold (TWC: Front Catalyst), No. 1 exhaust manifold heat insulator and No. 1 front floor heat insulator.
HINT:

At this time, do not install the parts with the bolts or nuts.
Temporarily install the exhaust manifold (TWC: Front Catalyst) to the cylinder head sub-assembly with 7 new nuts.
Tighten the 7 nuts in the order shown in the illustration.
Torque: 26 N.m (265 kgf/cm, 19 ft.lbf)

INSTALL MANIFOLD STAY
1. Fig 2: Manifold Stay Bolt And Nut Tightening Sequence
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. Temporarily install the manifold stay to the exhaust manifold (TWC: Front Catalyst) and cylinder block sub-assembly with the bolt and nut.
  2. Tighten the bolt and nut in the order shown in the illustration.
    Torque: 43 N.m (438 kgf/cm, 32 ft.lbf)

INSTALL NO. 1 FRONT FLOOR HEAT INSULATOR

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Torque Wrench Fulcrum Length

Using a 10 mm union nut wrench, install the No. 1 front floor heat insulator to the vehicle body with the 2 nuts.
Specified tightening torque

Torque: 4.9 N.m (50 kgf/cm, 43 in.lbf)

HINT:
- Calculate the torque wrench reading when changing the fulcrum length of the torque wrench.
  Refer to PRECAUTION [10/2022 - ]
- When using a 10 mm union nut wrench (fulcrum length of 22 mm (0.866 in.)) + torque wrench (fulcrum length of 162 mm (6.38 in.)): 4.3 N.m (44 kgf/cm, 38 in.lbf)

INSTALL NO. 1 EXHAUST MANIFOLD HEAT INSULATOR

Torque Wrench Fulcrum Length

Using a 10 mm union nut wrench, install the No. 1 exhaust manifold heat insulator to the exhaust manifold with the 3 bolts.
Specified tightening torque

Torque: 10 N.m (102 kgf/cm, 7 ft.lbf)

HINT:
- Calculate the torque wrench reading when changing the fulcrum length of the torque wrench.
  Refer to PRECAUTION [10/2022 - ]
- When using a 10 mm union nut wrench (fulcrum length of 22 mm (0.866 in.)) + torque wrench (fulcrum length of 162 mm (6.38 in.)): 8.8 N.m (90 kgf/cm, 78 in.lbf).

INSTALL WIRING HARNESS CLAMP BRACKET
Torque: 13 N.m (133 kgf/cm, 10 ft.lbf)
INSTALL AIR FUEL RATIO SENSOR (for Sensor 1)
Refer to INSTALLATION [10/2022 - 08/2023]
INSTALL OUTER COWL TOP PANEL SUB-ASSEMBLY
Refer to PROCEDURE - Step 18
INSTALL WINDSHIELD WIPER MOTOR AND LINK ASSEMBLY
Refer to INSTALLATION [10/2022 - ]
INSTALL FRONT EXHAUST PIPE ASSEMBLY (TWC: Rear Catalyst)

See step 1
ADD ENGINE COOLANT (for Engine)
Refer to PROCEDURE - Step 5
INSPECT FOR COOLANT LEAK (for Engine)
Refer to PROCEDURE - Step 1
INSPECT FOR EXHAUST GAS LEAK
If gas is leaking, tighten the areas necessary to stop the leak. Replace damaged parts as necessary.

HINT:

Perform "Inspection After Repairs" after repairing or replacing the exhaust system.

Refer to INITIALIZATION [10/2022 - ]
INSTALL FRONT FLOOR COVER LH
Refer to PROCEDURE - Step 19
INSTALL NO. 2 ENGINE UNDER COVER ASSEMBLY
Refer to PROCEDURE - Step 6