1999 Toyota Tacoma oxygen sensors, HOW MANY?

Hello,

Here is how the Banking on o2 sensors go.

Bank 1 Sensor 1 would be Passenger Side in the Exaust Manifold

Bank 1 Sensor 2 would be the next sensor back or in just before the Cat.

Bank 2 Sensor 1 Would be Driver Side in Exaust Manifold.

Bank 2 Sensor 2 would be next sensor back or infront of cat.( This would be on a dual exaust system)

On some vehicles there are 2 pipe that will go into the engine side of the cat and there will be an o2 sensor in each at the cat.

Any other would be after cat.

Hope this helped.

We Appreciate the Donation.

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