(Read entirely before removing sensor) So, I spent forever trying to find a thread that gave a step by step on how to take everything apart to get the sensor replaced. I'm not extremely mechanically inclined, and managed to do it in 5 hours. So be prepared to have the engine apart for several hours. But the best thing I could find on a step by step to get the intake manifold apart, to get to the sensor, was a supercharger manual to get the upper manifold off correctly with every bolt and nut that needs to be removed, as well as a diagram with the bolts needed to take out for the lower manifold.

• Here is the PDF to follow to get the upper manifold off. (I started at Step 15. Before that is relieving fuel pressure, disconnecting battery, and replacing the oil filter which I did not need.)
  https://www.quadratec.com/Assets/Ins...ion/200973.pdf
  Going step by step, skipping step 44, and finishing at 53 was the easiest. Step 40/41, I found it easiest to get access to the two nuts that are under and next to the battery-box, through the front passenger wheel well.
  To undo the lower intake manifold, I followed the diagram below, (with the sensor location). When undoing the fuel injectors and fuel rail, make sure to disconnect each connector along with the screws. There is also a connector on the back of the manifold that is next to the fire wall to be able to pull the manifold out, that way you have access to the sensor.
  (Lower manifold screw locations) https://www.2carpros.com/images/ques...5/original.jpg
  (Sensor location/Number 2 shown) https://www.2carpros.com/images/ques...7/original.jpg
  To put everything back into place, I just simply followed the steps in reverse, and viola. I used an oil switch socket that I had bought from O'Reilleys. Make sure to either buy a tree clip remover, or have something that works just as good, as you will be removing a lot of them. I do not know the torque specs exactly, just tightened enough, but not so tight to crack the plastic. Make sure everything is free of debris as well, before putting the upper and lower manifolds back together. I hope I'm not forgetting too much. But following these steps worked out for me. Good luck!

 

Old thread i know, still helpful 3 years later. I created this account to thank you as well as give an additional tip for assistance.

i recently followed this write up and got rid of my engine light.

my tip is, disconnect all plugs coming from fuel rails and pull up on the rails after unscrewing the screws holding them down. Note- a little fuel will dribble so have paper towel ready.

move rails aside to the right keeping the rail tube connected. Now its easier to remove the lower intake manifold as listed up via the 8 screws. Also, go to advance auto parts and be sure to replace the fuel injector gaskets, They sell packs of 4 for around $6 you need 6 gaskets. They sit around on the top on the injectors Before you put the rails back on.

 

The gift that keeps on giving. I'm about to undertake this as well. Much thanks for the info!