Where is the oxygen sensor on a Toyota Avalon?
The oxygen sensors on a Toyota Avalon are located in the exhaust system: typically two upstream sensors before the catalytic converter and two downstream sensors after the catalytic converter, one on each exhaust bank.
How the oxygen sensor system works in the Avalon
Oxygen sensors monitor the level of oxygen in the exhaust and help the engine control module optimize the air-fuel mixture for efficiency and emissions. Sensors placed both before and after the catalytic converter allow the system to monitor catalyst performance and adjust operation accordingly.
Exact locations by sensor type
The following list shows where you’re likely to find each sensor on a standard Avalon with a V6 engine. Note that the left-right orientation is from the driver’s seat perspective (Bank 1 is the bank containing the cylinder with the number one spark plug).
- Bank 1 Sensor 1 (upstream O2 sensor): installed in the exhaust manifold or the pipe leading from the manifold to the catalytic converter on the left bank (as you look from the front of the vehicle).
- Bank 2 Sensor 1 (upstream O2 sensor): installed in the exhaust manifold or pipe on the right bank, before the catalytic converter.
- Bank 1 Sensor 2 (downstream O2 sensor): located in the pipe after the Bank 1 catalytic converter, monitoring the cat's efficiency.
- Bank 2 Sensor 2 (downstream O2 sensor): located in the pipe after the Bank 2 catalytic converter.
Conclusion: The four sensors are distributed across the two exhaust banks, with upstream sensors close to the engine and downstream sensors after the catalytic converters. Access typically requires raising the vehicle and/or removing components to reach the sensors safely. Always let the exhaust system cool before service.
Notes for model-year variations
On common Avalon models produced for years around 2013–2018 (including standard gasoline and hybrid variants), the configuration is four oxygen sensors (two upstream, two downstream). If you are inspecting a different generation, verify with the official service manual or a reputable repair database for exact locations, as there can be minor layout differences.
Summary
In a Toyota Avalon, look for two upstream O2 sensors placed before the catalytic converters on each exhaust bank and two downstream O2 sensors placed after the catalytic converters. They’re typically accessible from beneath the vehicle or via the engine bay, depending on year and trim. For replacement or diagnostic work, ensure the engine is cool and follow proper safety procedures.
Can I replace my O2 sensor myself?
The ease of changing an oxygen sensor depends on how much space you have to work with. They're often stuck and require a special socket, a torch and a long breaker bar. You can rent all those tools. But if you can get good access, it can be a real bear to remove an old sensor.
How many oxygen sensors does a 2002 Toyota Avalon have?
Fits 2000-2004 for Toyota Avalon 3.0L O2 Sensors All 3 Required.
Where is the O2 sensor on a 2008 Toyota Avalon?
Your 2008 Toyota Avalon XL is equipped with four oxygen (O2) sensors. Location details are as follows: Bank 1 Sensor 1: Positioned on the exhaust manifold, nearest to the engine. Bank 2 Sensor 1: Positioned on the exhaust manifold, on the opposite side of the engine from Bank 1 Sensor 1.
How much does it cost to replace the oxygen sensor on a Toyota Avalon?
The average cost for a Toyota Avalon Oxygen Sensor Replacement is between $538 and $594. Labor costs are estimated between $92 and $135 while parts are priced between $446 and $458. This range does not include taxes and fees, and does not factor in your unique location.
