My vss circuit has a malfunction. I need to know what it is exactly, where to locate it, and how to change it? Not to mension, I would like to know a general price of the vss circuit.

Variable Speed Sensor (VSS), which is located on top of the transmission and fairly close to the firewall. Two small bolts (likely 8mm) secure it. Easy job to replace. Check prices for year and model at your local dealer or online.