2001 Tundra P0135 - O2 Sensor

[JeffKeryk]

Our trusty '01 Tundra 4.7 with 209K threw a P0135 trouble code. O2 Sensor, bank 1 upstream.
Amazon sent me the Denso for $47 all in, next day delivery. Easy peasy install and cleared the code.

These engines are real smoothies and ask for very little. But suck the freakin' gas!
Man she purrs even better now. Hopefully it improves the mileage if it was running in open loop before.

I was wondering if it makes sense to replace both upstream sensors?

 

[Marcozi]

Pre-cat sensors typically have a 100k mile lifespan. After that length of service they have a tendency to get lazy-they react slower to change sin the exhaust. My recommendation is replace both pre-cat sensors.

 

[JMJNet]

For $47, I would not think twice on replacing the other upstream.
Of course, that other sensor may be located in a more difficult location based on my experience.

 

[JeffKeryk]

For $47, I would not think twice on replacing the other upstream.
Of course, that other sensor may be located in a more difficult location based on my experience.

Thanks. The sensor is a straight shot; a long extension and the special socket breaks torque. The connector might be the hardest part and it ain't that bad. Maybe living in CA helps, as I have never had a real problem removing an O2 sensor.

 

[simple_gifts]

I'd did all (4) on a '02, and yes, the connector is tough. I just wanted to get replacing them 'out of the way' instead of chasing things piecemeal.

The Toyota dealer wanted $200 / sensor, not installed.

 

[Tomioka]

Thanks. The sensor is a straight shot; a long extension and the special socket breaks torque. The connector might be the hardest part and it ain't that bad. Maybe living in CA helps, as I have never had a real problem removing an O2 sensor.

I had to remove the headers to get to mine:

Yes these are crummy ebay headers that replaced the failure prone stock "manifolds" but they held up through work truck abuse for 10 years. I have JBA SS titanium coated headers on em now.

 

[JeffKeryk]

For $47, I would not think twice on replacing the other upstream.
Of course, that other sensor may be located in a more difficult location based on my experience.

I Amazon'ed another. Thanks for your advice.

 

[meep]

What’s wild is that they are HEADERS. These are short tube 4 into 1 headers, from the factory. I thought it was fancy to see that on mine, too. But there was a downside too, at upper rpm’s, such as towing heavy for a long distance, they aren’t…. quiet.