My starter spins but it sounds like it is not engaging so I put a new one on it and it did the same thing so I had a socalled mecanic give it a try and they put a starter on it and 400 dollars later it is wors then when I changed it if you hit the key 3 or 4 times it will roll over and start what do you think. It is a v6 motor withe starter on top under the intake manifold
As soon as the first replacement starter did the same thing the most likely suspect is teeth worn off the flex plate's ring gear. Engines tend to coast to a stop in the same place so the starter drive always slides into mesh with the same teeth. When rust builds up on the shaft, the starter drive is sluggish to engage and the motor can start spinning too soon. That puts a lot of stress on the edges of the teeth so they start to wear down.