TWC and Middle Pipe Installation Note

WARNING: This page is about a different car, the 2009 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

When newly replacing the TWC or the middle pipe, place alignment marks on the new part in the same position as the removed part.

Install the TWC to the middle pipe using the following procedure.
1. Align the TWC and the middle pipe alignment marks.
  
  Fig 1: Identifying Alignment Mark And Nut On TWC
  Courtesy of MAZDA MOTORS CORP.
2. Tighten the nut shown in the figure.
Tightening torque

41-51 N.m {4.2-5.2 kgf.m, 31-37 ft.lbf}

Fig 2: Identifying Alignment Mark And Nut On TWC
Courtesy of MAZDA MOTORS CORP.
Spray carbon remover (TB6601 or equivalent) on the flared section of the exhaust pipe.
Remove the carbon adhering to the flared section shown in the figure using a nylon brush or sandpaper (No. 400 or equivalent)

Fig 3: Identifying Flared Section

Courtesy of MAZDA MOTORS CORP.