Where is the oxygen sensor on a 2009 Honda Odyssey?
The oxygen sensor layout on a 2009 Honda Odyssey typically includes four sensors: two upstream (pre-catalytic) and two downstream (post-catalytic), one pair for each bank of the V6 engine.
In practical terms, the upstream sensors are mounted on the exhaust manifolds just ahead of the catalytic converters, while the downstream sensors sit on the exhaust pipe after the converters. Access can be from the engine bay or underneath the vehicle, depending on trim and shielding. This arrangement helps the engine computer fine-tune the air-fuel mixture and monitor catalytic efficiency for emissions compliance.
Sensor locations by position
The following sections break down where the oxygen sensors are typically located on the 2009 Odyssey, separated into upstream and downstream positions for clarity.
Upstream (pre-catalytic) sensors
These two sensors monitor exhaust before the catalytic converters and feed data to the engine control module to adjust fuel trim in real time.
There are two upstream sensors on a V6 Odyssey—one for each bank. The typical mounting points are:
- Bank 1 Sensor 1 (Upstream) — mounted on the Bank 1 exhaust manifold, just before the corresponding catalytic converter (or on the pipe immediately downstream of the manifold).
- Bank 2 Sensor 1 (Upstream) — mounted on the Bank 2 exhaust manifold, just before the corresponding catalytic converter.
Access to these sensors is usually from the engine bay side, though shields or heat protection may require some disassembly to reach the sensor and its connector. When replacing, use the correct socket and apply anti-seize on reinstall.
Downstream (post-catalytic) sensors
These sensors monitor the efficiency of the catalytic converters by measuring the exhaust after the catalysts.
There are two downstream sensors on the 2009 Odyssey, one per bank. Typical mounting points are:
- Bank 1 Sensor 2 (Downstream) — located on the exhaust pipe after the Bank 1 catalytic converter.
- Bank 2 Sensor 2 (Downstream) — located on the exhaust pipe after the Bank 2 catalytic converter.
Downstream sensors are generally positioned further back along the exhaust path and may require lifting the vehicle or removing protective panels for full access. For replacements, verify sensor compatibility (heated sensors are common) and follow torque specs from the service manual.
Tips for locating and replacement
If you’re planning to replace or test the sensors, here are quick guidelines to locate and prepare:
- Park on a level surface, engage the parking brake, and allow the exhaust to cool before working on it.
- Trace the exhaust from the engine area toward the rear to locate the manifold-mounted (upstream) sensors, then follow to the catalytic converters and back along the pipe for the downstream sensors.
- Consult the service manual for exact sensor part numbers, torque specs, and wiring harness routing to avoid damage during removal or reinstallation.
Proper access and careful handling reduce the risk of damaging sensors or wiring harnesses during maintenance.
Summary
In the 2009 Honda Odyssey, expect four oxygen sensors: two upstream sensors (one for each bank, before the catalytic converters) and two downstream sensors (one for each bank, after the converters). They are positioned on the exhaust manifolds and then along the exhaust pipes, with access varying by trim and shielding. Accurate replacement and testing require consulting the vehicle’s service manual and using the correct tools and torque specifications. This setup supports real-time fuel management and emissions monitoring.
Where is the oxygen sensor located in the Honda Odyssey?
Okay so here's the back of the motor. See this little sensor right there with the wiring harness we're going to undo that using our oxygen sensor socket and then follow this pigtail.
How many O2 sensors does a 2009 Honda Odyssey have?
Is the downstream sensor that sniffs the output of the catalytic converter to ensure it's working properly. That's all it does it doesn't affect anything else.
What are the symptoms of a bad O2 sensor on a Honda?
Here are a few symptoms of bad or failing 02 (oxygen) sensors: The check engine light may come on. Poor fuel efficiency: You may notice a decrease in gas mileage. Bad smells: You may smell something rotten or sulfurous from the exhaust. Black smoke: You may see black smoke coming from the exhaust.
How much does it take to change an O2 sensor on a 2009 Honda Odyssey?
The average cost for a Honda Odyssey Oxygen Sensor Replacement is between $594 and $756. Labor costs are estimated between $76 and $111 while parts are priced between $518 and $645. This range does not include taxes and fees, and does not factor in your unique location. Related repairs may also be needed.
