Replacing the upstream O2 sensors.
Part #s:
DENSO 234-4738 O2 Sensor, Upstream Right
DENSO 234-4742 O2 Sensor, Upstream Left
These are the connectors. The black connector is the right side, and the grey one is the left side.
Both O2 sensor male connectors are attached to the top rear center of the engine via metal "L" brackets and a single bolt. The vehicle wiring harness female connectors are on top, and must be removed first.
The "L" brackets must be removed from the old O2 sensors and attached to the new ones.
The right side O2 sensor is accessible from the top of the engine compartment.
The left side O2 sensor is accessible from below the vehicle by the front wheel.
You'll most likely need to use an O2 sensor socket and a healthy dose of penetrant to loosen them.
I destroyed both of mine in the process of removing them as they were so tight.
The Denso O2 sensors come with a packet of high temp anti-seize with which you'll want to coat the threads.
Be careful to keep the sensor tip clean and away from any sort of silicone.
Part #s:
DENSO 234-4738 O2 Sensor, Upstream Right
DENSO 234-4742 O2 Sensor, Upstream Left
These are the connectors. The black connector is the right side, and the grey one is the left side.
Both O2 sensor male connectors are attached to the top rear center of the engine via metal "L" brackets and a single bolt. The vehicle wiring harness female connectors are on top, and must be removed first.
The "L" brackets must be removed from the old O2 sensors and attached to the new ones.
The right side O2 sensor is accessible from the top of the engine compartment.
The left side O2 sensor is accessible from below the vehicle by the front wheel.
You'll most likely need to use an O2 sensor socket and a healthy dose of penetrant to loosen them.
I destroyed both of mine in the process of removing them as they were so tight.
The Denso O2 sensors come with a packet of high temp anti-seize with which you'll want to coat the threads.
Be careful to keep the sensor tip clean and away from any sort of silicone.
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