P0031 Bank 1...

Recently had an intermittent check engine light. I have discovered that it is throwing code P0031, which I understand is a faulty Air Fuel sensor Bank 1 Sensor 1. Was about to order a part then realized that I’m not sure what side Bank 1 is. Found a thread on TW that said Bank 1 is passenger side but is the passenger side left or right? Seems simple but if someone could point me in the correct direction would be greatly appreciated!!

 

Bank one is the passenger side. Look for leaks first.

 

Passenger side is passenger side. Bank 1 is the first sensor of the two so the one which is closest to the exhaust manifolds. It's a pain in the rear to get to, not as much as bank 2 sensor 1 though.

 

Understood, thanks for the info so far. The question I’ve got is when ordering the part it is labeled left or right. Not passenger/ driver. I’m just double checking to make sure, seen heard conflicting information. Passengers side/ bank 1 = left?

 

Post #3 here shows Bank 1 on Passenger Side.
https://www.tacomaworld.com/threads/o2-sensor-location.475144/

 

Pretty sure passenger side = right

 

Right upstream.

Denso is best choice.

 

Perfect thank you!

Exactly what I needed to know thank you.

You guys are lifesavers

 

Any V block motor that I've seen has the cylinders staggered. The forward most cylinder is always #1

 

You could also swap bank 1 and 2 sensors and see if the code follows to verify the sensor is bad.

 

Thanks for the tip!

True didn’t thing of that, I figured they were the same sensor just the length of the connector on one side is shorter than the other.