where is the ECT sensor located on a 2009 trailblazer?
It is not behind the alternator in the engine block.
Haha, been looking above the thermostat have ya? It changed locations in 06. It's located on passenger side, wayyyy in the back at the block. Pretty difficult to access, which is why my new sensor is still in a box. My 03 was cake, above the t-stat, but 06+ is a PIA. Why do you want to change it?