Engine Controls - Engine Knock at Idle
ENGINEEG014-07
Title:
ENGINE IDLE KNOCK NOISE
Models:
'07 LS 460/460L
June 28, 2007
Introduction
Some 2007 model year LS 460 vehicles may exhibit a knocking noise originating from the engine compartment that is most noticeable under the following conditions:
^ Engine idling at operating temperature
^ A/C OFF
^ A/T in "D" range
The Engine Control Module (ECM) (SAE term: Powertrain Control Module/PCM) logic, valve lash adjusters, and the No. 3 timing chain tensioner have been modified to improve this condition. Please use the repair procedure below to address customer concerns.
Applicable Vehicles
^ 2007 model year LS 460/460L vehicles produced BEFORE the Production Change Effective VINs shown below.
Production Change Information
Warranty Information
Applicable Warranty:*
This repair is covered under the Lexus Federal Emissions Warranty. This warranty is in effect for 96 months or 80,000 miles, whichever occurs first, from the vehicle's in-service date.
* Warranty application is limited to correction of a problem based upon a customer's specific complaint.
Parts Information
Calibration Identification Chart
Required Tools & Equipment
Repair Procedure
Determine the ECM (PCM) calibration ID for the vehicle.
^ If calibration ID 35036000 (previous calibration ID) is present go to Repair Procedure A.
^ If calibration ID 35036100 (NEW calibration ID) is present go to Repair Procedure B.
Repair Procedure A
1. Check for the Authorized Modifications Label affixed to the vehicle in the location shown in Figure 1. Confirm if the ECM (PCM) calibration has been updated.
If the calibration ID listed is NOT the latest ECM (PCM) calibration go step 2. If the calibration ID listed is the latest ECM (PCM) calibration go to Repair Procedure B.
2. Flash reprogram the ECM (PCM).
^ The GR8 Battery charger MUST be used in Power Supply Mode to maintain battery voltage at 13.5 volts while flash reprogramming the vehicle.
^ For details on how to use the GR8 Battery charger please refer to the GR8 Instructions Manual, located on the Technical Information System (TIS), Diagnostics - Battery.
Follow the procedures outlined in TSIB No. SS002-07, "Techstream ECU Flash Reprogramming Procedure, " and flash the ECM (PCM) with the NEW calibration file update.
3. Install the Authorized Modifications Label.
A. Using a permanent marker, enter the following information on the label:
^ ECM (PCM) part number: [Refer to the Parts Information section for the CURRENT PART NUMBER]
^ Calibration ID(s): [Refer to the Calibration Identification Chart for the NEW CALIBRATION ID]
^ Dealer Code
^ Repair Date
^ Change Authority (this TSIB number): EG014-07
B. Affix the Authorized Modifications Label to the vehicle at the location shown in Figure 1. The Authorized Modifications Label is available through the MDC, P/N 00451-00001-LBL.
4. Confirm that the ECM recalibration addressed the customer concern. If the knocking noise is gone, the repair is complete. If the noise is still present, go to Repair Procedure B.
Repair Procedure B
1. Replace the No.3 timing chain tensioner and both No.1 cylinder intake valve lash adjusters.
Refer to TIS, 2007 model year LS 460 Repair Manual,
^ Engine/Hybrid System - Engine Mechanical - "1UR-FSE Engine Mechanical: Camshaft (for Bank 1): Removal"
^ Engine/Hybrid System - Engine Mechanical - "1UR-FSE Engine Mechanical: Camshaft (for Bank 1): Installation"
2. Reconnect the negative (-) battery terminal.
3. Re-initialize any affected power systems.
Refer to TSIB No. PD007-07, "Power System Initialization During PDS".
4. Test drive the vehicle to confirm that the knocking noise is NO longer present.