Engine Controls - MIL ON/Multiple DTC's Set, Runs Rough On Star

L-SB-0045-12

June 11, 2012

MIL "ON" DTC P030 # and/or Runs Rough on Cold Start

Service Category
Engine/Hybrid System

Section
Engine Control

Market
USA





Applicability

Introduction

Some 2010 - 2012 model year RX 450h vehicles may exhibit one of more of the following conditions:

^ MIL "ON" with DTC P0300, P0301, P0302, P0303, P0304, P0305, and/or P0306 present

^ Rough running on initial start-up after a cold soak

Follow the procedure in this bulletin to address these conditions.





Warranty Information

Parts Information

Required Tools & Equipment

Repair Procedure

1. Confirm the engine runs rough on initial start-up after a cold soak or any of the following DTCs are present:

^ P0300 - Random/Multiple Cylinder Misfire Detected

^ P0301 - Cylinder 1 Misfire Detected

^ P0302 - Cylinder 2 Misfire Detected

^ P0303 - Cylinder 3 Misfire Detected

^ P0304 - Cylinder 4 Misfire Detected

^ P0305 - Cylinder 5 Misfire Detected

^ P0306 - Cylinder 6 Misfire Detected

If other DTCs are present, this bulletin does NOT apply. Continue diagnosis per Repair Manual procedures.

2. Perform misfire diagnosis.

Refer to the Technical Information System (TIS), applicable model year RX 450h Repair Manual:

^ 2010 (to 08/2009)/2010 (from 08/2009)/2011/2012 RX 450h:
Engine/Hybrid System - Engine Control - "2GR-FXE Engine Control: SFI System: P0300-P0306: Random/Multiple Cylinder Misfire Detected"

3. If no concerns are noted with the mechanical engine condition, engine control system, ignition system, or fuel supply system, remove the fuel injectors and visually inspect the fuel injector tips for signs of debris.

Is there debris on any of the fuel injector tips?

^ YES - Replace all six fuel injectors. Go to step 4.

^ NO - This bulletin does NOT apply.

4. Replace the fuel injectors.

Refer to TIS, applicable model year RX 450h Repair Manual:

^ 2010 RX 450h:
Engine/Hybrid System - Fuel System - "2GR-FXE Fuel: Fuel Injector: Removal (to 08/2009)/Removal(from 08/2009)/Installation (to 08/2009)/Installation (from 08/2009)

^ 2011 RX 450h:
Engine/Hybrid System - Fuel System - "2GR-FXE Fuel: Fuel Injector: Removal/ Installation"

^ 2012 RX 450h:
Engine/Hybrid System - Fuel System - "2GR-FXE Fuel: Fuel Injector: Removal/ Installation"

5. Clear all stored DTCs.

6. Start the engine and confirm the repair.

© 2012 Lexus, a division of Toyota Motor Sales, USA