I spent hours in engine and on the internet. I viewed 15 different sites with 15 different answers. Finally found it...The crankshaft position sensor on a 2009 Chevy Traverse (3.6 liter) is as follows: You need to jack up vehicle (or use ramps) and climb under. You CANNOT access it from top (as many sites state). On the firewall (vehicle) side of motor, in the center, directly below the exhaust outlet, you will see a silver (aluminum) heat cover/plate. It is held on by 2 bolts. (one 15mm and one 10mm). The sensor is located benind this cover. Once you get this cover off, you will see two seperate sets of wires, wrapped in silver heat deflection tape. The set of wires that extends further to the left go to th CPS (sensor). I used a small extendable automotive mirror to see it. It is in a tight spot, but once you find it, it is easier to access than it looks!!! You must unbolt old sensor (10mm bolt) and remove it, prior to disconnecting wire, as it is nearly impossible to disconnect wire first. It is held on by a small red lock clip.Took me about 30 minutes total to switch it out. Hope this helps !!! Good luck.