Warm Engine Tapping or Sewing Machine type Sound from Left Cylinder Head – 2012-2013 Subaru

NUMBER: 02-146-13R
DATE: 10/07/13
REVISED: 02/05/15

APPLICABILITY: 2012-13MY Impreza 2.0L
2013MY XV Crosstrek
SUBJECT: Revised Valve Train Parts to Reduce a Warm Engine Tapping or Sewing Machine type Sound from the Left Cylinder Head



This bulletin announces the availability of revised valve train components developed to reduce a tapping sound which may be heard coming from the left-hand (B2) side of the engine when the engine is warm.  This bulletin does not address any cold engine or start-up sounds.  The changes consist of:


In addition, the insulator pad has been eliminated from the B2 intake manifold protector.



VEHICLE Model Starting VIN / Production Date
Impreza and XV Crosstrek 4-Door D*005801 / August 8, 2012
5-Door D*209069 / August 22, 2012

NOTE: 2013MY 5-Door models with the 12th VIN character = ”8” (e.g D*8*****), are all AFTER this countermeasure.



INTAKE VALVE Part Number 13201AA670 13201AA640
Change Valve stem length:


Valve stem length:


Identification I31 I22
EXHAUST VALVE Part Number 13202AA750 13202AA670
Change Valve stem length:


Valve stem length:


Identification E3 E2
VALVE ROCKER Part Number 13249AA250 13249AA240
Change Change to roller portion
Identification Circular groove added on pivot side No groove
PIVOT, ROCKER ARM Part Number 13296AA090 13296AA051
Change Not specified

These revised Pivots have been installed during production starting

with VIN: D*005801 Impreza (4-Door)

D*209069 Impreza and XV Crosstrek (5-Door)

CAMSHAFT INTAKE, LEFT Part Number 13037AA940 13037AA860
Change Cam profile change
Identification 38B340 or 38B390 38B260 or 38B310
CAMSHAFT EXHAUST, LEFT Part Number 13052AA940 13052AA860
Change Cam profile change
Identification 53B340 or 53B390 53B260 or 53B310


The illustrations below show additional information about the changes to the valve rockers, camshafts and valves to help readily distinguish them from the previous version parts.

changes to the valve rockers, camshafts and valves




If you receive a customer concern of a tapping sound from the B2 cylinder head, confirm it is isolated to the B2 valve train area before proceeding with any repairs.  Once verified, order and replace all 4 intake and all 4 exhaust valves, all 8 rockers, both the intake and the exhaust camshaft and all 8 rocker arm pivots (Replace the rocker arm pivots only if the VIN is prior to the listed VIN breakpoint shown in the Parts Information area of this bulletin) as a set using the part numbers shown in this bulletin (in addition to the necessary gaskets and seals). Refer to the service procedures outlined in the applicable Service Manual for installation.


NOTE:  When resetting the valve clearances, the intake should be set to 0.13mm +0.02 / – 0.03 and the exhaust should be set to 0.22mm +/- 0.02.  These are revised specifications and not reflected in the Service Manual.

IMPORTANT:  Do not mix old and new parts together or mix parts between the left and right cylinder head as it will become impossible to obtain valve clearances that are within specification.

TIP: An egg carton makes a perfect organizer tray. Make sure to mark it as necessary (front, intake, exhaust) to eliminate any mixing of parts.



For vehicles within the Basic New Car Limited and/or Powertrain Warranty, this repair may be claimed using the following information:

Engine R&R for Cylinder Head Servicing B293-110 ABH-48 5MT 2.7
CVT 3.0
L/H Cylinder Head &/or Gasket R&R C293-112 4.9
Valves- Replace C293-123 1.6
Valve Train Noise Diagnosis C243-001 0.3

REMINDER:  SOA strongly discourages the printing and/or local storage of service information as previously released information and electronic publications may be updated at any time.

  • Always refer to STIS for the latest service information before performing any repairs.


Leave A Comment

Your email address will not be published. Required fields are marked *


This site uses Akismet to reduce spam. Learn how your comment data is processed.