Sentra L4-2.5L (QR25DE) (2003)
11.
Disconnect the Oxygen Sensor Wire Harness Connector (see Figure E8).
12.
Remove the Oxygen Sensor Wire Harness from the Upper Front Exhaust Manifold/Catalyst Heat Shield Clips.
Remove Upper Front Exhaust Manifold/Catalyst Heat Shield:
IMPORTANT:
If you break off a heat shield screw(s) in an Exhaust Manifold/Catalyst that is supposed to be re-used on the vehicle, perform Procedure G -
Install Keen-Sert(s) As Needed.
13.
Remove Upper Front Exhaust Manifold/Catalyst Heat Shield:
^
Carefully remove four screws that secure the Heat Shield (see Figure E9).
^
IMPORTANT:
Use "penetrating" oil. Loosen screws 1A turn with hand-tool (do not use power tool) and apply penetrating oil before removing screws
completely.
^
Remove the Heat Shield
Remove Front Exhaust Pipe:
NOTE:
You may have already removed the Front Exhaust Pipe in Procedure D. If so, proceed with step 17.