This is just a FYI to anyone that gets a P1131 code and decides to replace their up stream O2 sensor on the passenger side. I just did mine and it's a pain. But here is the best way to do it.

First off parts and tool list.
1. AutoZone Bosh Upstream 02 sensor. ( Like $50 tax and all)
2. AutoZone 22mm open end/boxed end wrench. ( $7.00) (7/8 wrench is too big and will slip!)
3. Wire cutters
4. 5/16 socket with a 1/4 drive and a 4-inch extension.
5. Good bright flashlight. ( I used a small LED Kind)
6. Tools to remove your front tire.

Sensor removal procedure.
1. Grind off or cut off the Box end of the 22mm wrench. It's only 7 bucks.
2. Jack up front of car and make sure it's not going to fall on you.
3. Remove the wheel.
4. Remove the 5/16 screw holding the transmission dipstick tube. Small bracket right above the top of your shock.
5. Wiggle the dipstick tube out from the top of the engine. Just move it up and out of the way by 5 inches or so. This will let you get to the O2 sensor Plug.
6. Get under the car and cut the 4 wires above the O2 sensor. Or if you can't see yourself cutting the wires try to disconnect the plug.
7. Slide the 22mm open-ended wrench onto the O2 sensor. Loosen up sensor.
8. As soon as I loosened up my sensor it came off with my hand.
9 Now try to remove the plug. ( Good luck here! Just push down on the tab and pull on the plug and wire. It's a pain)
10. Now you have the plug and the sensor off and you have about two or three cuts on your hand and you have cussed enough for a week.

Sensor installation.
1. Screw the new sensor in. Now to get the sensor in tight you will now know why I said to grind off the box end of the wrench. It will give you enough room without bumping into the heat shield. It's still a very tight fit.
2. Plug the sensor into the plug. (This is about the hardest thing to do! I was sitting in my wheel well to do this. I managed to hold both plugs in one hand and slip them together. You will feel it snap together).
3. Make sure no wires are up against the exhaust.
4. Go under the car and connect the transmission dipstick tube to the transmission.
5. Install the 5/16 screws.
6. Put your tire back on and drop the truck.

Last notes.. You can try doing it with your wheel and dipstick on but good luck. Also if you want to save time just cut the wires above the sensor when removing the O2 sensor It will make removing the sensor and plug an easy task.


You are done! Beer time...

 

Or, you could remove the tire, reach through the wheel well and remove it.

BTW, nice write-up.

 

Or not remove the tire and just lay under your truck; my GOD