Visual inspection didn't show any cracks that I can tell. After removing all belts (had previously removed the supercharger belt and have been running it without for about a week to no change), and running the vehicle the noise is no doubt coming from the harmonic balancer pulley. A friend suggested that might be the cause before I considered the flexplate but I didn't think anything of it. So, could this just be a bad harmonic balancer pulley? Also, I had problems with the tach dropping to zero while driving and the TCS light coming on right after, restarting the car fixed the issue. Hasn't done it in awhile, but it did it again yesterday. Someone on these forums suggested that might be caused by a faulty crankshaft position sensor. Could these two things be related? The knocking and the sensor? Could the sensor going out cause the vehicle to knock in the area of the harmonic balancer pulley?
