Canada - Engine Control - Engine Pinging Or Knocking Noise

Bulletin
TSB3034

Issue Date
July 3, 2008

Market
Canada

Title
Engine "Pinging" or "Knocking" Noise

Component
Engine Mechanical

Models
'01-'03 Sienna

TSB REVISION NOTICE:
- November 26, 2008: 2003 model year has been added to Applicable Vehicles. Warranty and Parts Information have been updated.
The previous TSB should be discarded.

INTRODUCTION:

Some 2001 - 2003 model year Sienna vehicles equipped with a 1MZ-FE engine may exhibit an intermittent "pinging" or "knocking" noise when accelerating slowly up a grade. The Engine Control Module (ECM) (SAE term: Powertrain Control Module/PCM) logic has been modified to improve this condition. Use the following procedure to address customer concerns.






APPLICABLE VEHICLES:






PARTS INFORMATION:






WARRANTY INFORMATION:

INSPECTION PROCEDURE:

1. Drive the vehicle slowly up a slight grade using light throttle input.
2. If engine "pinging" or "knocking" can be heard between 1400 - 1800 rpm, follow the procedure below to resolve the customer's concern.

REPAIR PROCEDURE:







1. Remove and replace the ECM (PCM).
2. Start the engine and warm it up to normal operating temperature before test driving.
3. Test drive the vehicle to confirm normal operation. The repair is complete.

NOTE:
Issue of this Technical Service Bulletin is to ensure that proper repair information is available. IT DOES NOT CONSTITUTE AN AUTHORIZATION FOR REPAIR. Normal provisions of the formal warranty policy, as applicable, will apply.