03-06 Nissan 350z Test pipes with Built in mechanical O2 sensor fix

Before you begin, allow engine to cool down. Spray down all bolts & nuts with WD-40 (or similar) and allow it to soak into the threads. The nuts & bolts will seize themselves onto the threads and spaying them down with Liquid Wrench or similar will make it much easier to remove the nuts & bolts.
- Test pipes laid out & test pipes laid out w/ additional wide band O2 ports.
- Close up detail of mechanical O2 sensor fix
- Remove 3 14mm nuts at exhaust manifold/catalytic converter flange. There are three nuts holding the catalytic converter to the exhaust manifold. Two nuts are facing the ground on one side of the flange, the third nut is on the opposite side of the flange. Use a 14mm stubby wrench or “S” wrench to remove the third nut. Repeat for other side.
- Remove the two 14mm nuts at the Y-pipe & cat flange. Repeat for other side.
- Unplug & unclip left & right oxygen sensor plugs
- Remove Catalytic converter bracket. Two 14mm nuts, two 14mm bolts.
- Remove Catalytic Converters
- Using a 22mm wrench, remove the oxygen sensor from the catalytic converter. Repeat for other side.
- Reinstall the factory O2 sensors into the O2 sensor bung.
- Reinstall test pipes using supplied M10X1.25 bolts & nuts.

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