Engine - Rattle/Knock Below 2000 RPM

Bulletin No: 01-053/10

Last Issued: 12/02/2010

Subject
RATTLE NOISE FROM ENGINE DUE TO STRETCHED TIMING CHAIN

APPLICABLE MODEL(S)/VINS
2007-2011 CX-7 2.3L Turbo vehicles with VINS lower than JM3ER******352482 (prod. before Sept. 29, 2010)

2007-2011 Mazdaspeed3 vehicles with VINS lower than JM1BL******398222 (prod. before Sept. 29, 2010)

2006-2007 Mazdaspeed6

DESCRIPTION

With the engine warmed up, some vehicles may exhibit a knocking/rattle type noise from the front timing cover and/or valve (cylinder head) cover below 2,000 rpm.

The noise is caused by excessive stretching of the timing chain.

Customers having this concern should have their vehicle repaired using the following repair procedure.

REPAIR PROCEDURE

1. Verify proper oil change intervals have been performed.

2. Verify that the noise is coming from the front timing chain cover and/or cylinder head area.

TIPS:
^ The noise is heard inside the vehicle with all of the windows rolled up, all accessories turned off, and engine running at normal operating temperature.

^ Knock pulse is at camshaft speed (1/2 the engine RPMs).

^ Knock can usually be felt on the No. 3 engine mount.

3. Remove the engine front cover according to the online MS3 instructions or the Workshop Manual (section 01-10 TIMING CHAIN REMOVAL/INSTALLATION).





4. Check the protrusion length of the chain adjuster plunger.

- If it is 17mm (9 exposed notches) or more, replace the timing chain with a modified one according to the online MS3 instructions or the Workshop Manual (section 01-10 TIMING CHAIN REMOVAL/INSTALLATION).

NOTE:
DO NOT replace the chain adjuster.

- If it is less than 17mm, the noise is not the result of the timing chain stretching concern. Refer to the "ENGINE NOISE" diagnostic procedure in TSB 01-036/10 "DIAGNOSTIC PROCEDURE FOR ENGINE NOISE REPAIR".

5. Verify repair.





PART(S) INFORMATION





WARRANTY INFORMATION

NOTE:
^ This warranty information applies only to verified customer complaints on vehicles eligible for warranty repairs.

^ This repair will be covered under Mazda's New Vehicle Limited Warranty term for a Powertrain Component.

^ Additional diagnostic time cannot be claimed for this repair.