Sometimes when I start my car, I can hear the starter motor just spinning. There's a low pitched whine coming from under the hood and the engine doesn't start. If I stop, wait for it to spin down, and turn the key again, most of the time, the motor will crank the engine. Other times, the motor will stick on. I'll turn the key, the engine will start, I release the key, and the starter keeps running. It also sometimes sticks on when it spins freely. I assume the sticking on is caused by a faulty starter solenoid, but before I chase that down and replace it, what causes the motor to spin freely and not crank the engine sometimes? Should I just replace the starter and the solenoid? Also, where is the solenoid located on the 3.1 v6? I've worked on ford trucks before where the solenoid was mounted remotely under the hood, but I'm not sure where to find it on the bird.