Caution / Notice / Hint

WARNING: This page is about a different car, the 2025 Lexus NX 350h, 2024 Lexus NX 350h, 2023 Lexus NX 350h, and 2022 Lexus NX 350h. However, it is still accessible from the selected car via links, so may be relevant.

The necessary procedures (adjustment, calibration, initialization or registration) that must be performed after parts are removed and installed, or replaced during exhaust manifold (TWC: Front Catalyst) removal/installation are shown below.

NECESSARY PROCEDURES AFTER PARTS REMOVED/INSTALLED/REPLACED

Replaced Part or Performed Procedure	Necessary Procedure	Effect/Inoperative Function when Necessary Procedure not Performed	Link
Replacement of air fuel ratio sensor (sensor 1) Gas leak from exhaust system is repaired	Perform Inspection After Repair	Poor idle, etc. Engine start function, etc.	Refer to INITIALIZATION [11/2021 - ]

WARNING:

To prevent burns, do not touch the engine, exhaust manifold or other high temperature components while the engine is hot.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

To prevent burns, do not touch the engine, exhaust pipe or other high temperature components while the engine is hot.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

COMPONENTS (REMOVAL)

Fig 1: Exhaust Manifold Removal Components [11/2021 - 03/2022] (1 Of 2)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Callout - Procedure		Part Name Code
1	NO. 2 ENGINE UNDER COVER ASSEMBLY	51420	-	-	-
2	ENGINE UNDER COVER HEAT INSULATOR	51468B	-	-	-
3	FRONT EXHAUST PIPE ASSEMBLY (TWC: Rear Catalyst)	17410	See step 3	-	-
4	HOOD TO FRONT FENDER SEAL LH	53389B	-	-	-
5	HOOD TO FRONT FENDER SEAL RH	53388D	-	-	-
6	WINDSHIELD WIPER MOTOR AND LINK ASSEMBLY	-	-	-	-
7	COWL VENTILATOR SPLASH SHIELD	55752A	-	-	-
8	COWL VENTILATOR PANEL SUB-ASSEMBLY	55704B	-	-	-

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Non-reusable part

Fig 2: Exhaust Manifold Removal Components [11/2021 - 03/2022] (2 Of 2)

Callout - Procedure		Part Name Code
9	AIR FUEL RATIO SENSOR (for Sensor 1)	89467B	See step 9	-	-
10	WIRE HARNESS CLAMP BRACKET	82715	See step 10	-	-
11	NO. 1 EXHAUST MANIFOLD HEAT INSULATOR	17167	See step 11	-	-
12	NO. 1 FRONT FLOOR HEAT INSULATOR	58151	See step 12	-	-
13	MANIFOLD STAY	17118	See step 13	-	-
14	NO. 2 WATER BY-PASS PIPE SUB-ASSEMBLY	16207	-	-	-
15	FLOW SHUTTING VALVE (WATER BY-PASS HOSE ASSEMBLY)	16260	-	-	-
16	EXHAUST MANIFOLD (TWC: Front Catalyst)	17141	See step 16	-	-
17	EXHAUST MANIFOLD TO HEAD GASKET	17173	-	-	-
18	NO. 2 EXHAUST MANIFOLD HEAT INSULATOR	17168	-	-	-

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Non-reusable part