One problem related to crankshaft position sensor has been reported for the 2007 Chevrolet Trailblazer. The most recently reported issues are listed below.
Vehicle stalls and shuts down everyday. Sometimes just stalls then accelerates, sometimes shuts off and I can switch to neutral and restart while coasting. Other times I get shutdown warning light and engine will not restart. I have to coast to the shoulder and wait. Engine will then struggle to restart and engine shakes violently. I wait a few minutes and it will start and run fine, sometime with check engine light on, sometimes not. Rpm gauge works sometimes, sometimes not. At time there has been no response when turning key to start. On going issue!! crankshaft position sensor has been replaced 3 times, and issue still persist. Major safety issue!!.