One problem related to crankshaft position sensor has been reported for the 2004 Chevrolet Trailblazer. The most recently reported issues are listed below.
Car felt "stuck" in gear, wouldn't accelerate, low on transmission fluid. Added more fluid, replaced speed sensor, camshaft & crankshaft sensors. Still having issues with rpms going high, car slamming from one gear into another. Also cannot run heat while driving, fan draws power & causes engine to stall out. Car also burning through gas very quickly.