Two numbers define the answer: the 2007 Accord with the 2.4-liter inline-4 typically uses two oxygen sensors, while the 3.0-liter V6 usually uses four. The exact count can vary by engine and market, with hybrids or specialized trims potentially differing from the gasoline-only models.
Sensor count by engine type
To avoid ambiguity, here is how the oxygen-sensor count typically breaks down by the engine configuration offered in the 2007 Accord lineup.
2.4-liter inline-4 engine
In most 2007 Accords powered by the 2.4L four-cylinder, there are two O2 sensors in the exhaust system: one upstream (before the catalytic converter) and one downstream (after the catalytic converter).
- Two O2 sensors total: one upstream and one downstream.
Conclusion: This engine configuration uses two oxygen sensors.
3.0-liter V6 engine
For the 2007 Accord with the 3.0L V6, there are typically four O2 sensors: two upstream sensors (one on each bank, before their catalysts) and two downstream sensors (one on each bank, after the catalysts).
- Four O2 sensors total: two upstream and two downstream, one on each bank.
Conclusion: This engine configuration uses four oxygen sensors.
Notes on variants
Hybrid models or regional variants may use additional sensors related to the hybrid system, emissions controls, or different exhaust layouts. The numbers above reflect the standard gasoline-engine configurations commonly found in North American 2007 Accord models.
Summary
Answer in brief: two O2 sensors on the 2.4L four-cylinder, four O2 sensors on the 3.0L V6. When in doubt about your exact trim or market, check the service manual or inspect the exhaust system to verify sensor locations and counts for your vehicle.