Car will not start

V8 four wheel drive automatic 180,000 miles

had car for over four years. Never had a problem with car until now, the car is turning over but not starting. Got the battery checked and the alternator and it was not either of two. The gas is on a half tank. Whats wrong with the car?

Okay, so about a week ago I had my alternator replaced. Last night, I was driving and went over a small bump and my brake and battery light came on at the same time. Within a few seconds my tachometer flipped out and stopped working, but the car kept driving me home (less than one mile). After turning the car off, it refused to start. Sometimes it just would not start with no sound other than like it was dying (two seconds trying to start then car would shut off, then lights and everything came back on) and other times I would hear one click, two clicks, or four to five clicks. Any help on what this could be? Thank you!

Well the last time the alternator failed, my dash lights would dim and other electrical components would slow like electrical seat, etc. After a day or two of the repaid all the electrical components were back to normal almost as if the alternator charged it back up. This time, I never got a dim light or any strange activity, just out of nowhere the dash lights and tachometer went crazy.

I had the Alternator tested after I replaced it and Advance told me it was working properly.

Voltage Regulator?

I raised the vehicle and removed the left front wheel to check the brakes, after inspection was okay. I replaced the wheel and let the vehicle down and hooked the negative battery cable back up and turned the key on and reset the security code. I then started the vehicle and put it in drive to move it forward to remove the block from the back wheel, put it in park and removed the chock, got back in and put it in drive to go forward and moved forward a few feet and went to put it in park and it stayed in D4, but the shift lever moved into park and the indicator started flashing in D4. The manual said to put key in the slot next to the shifter and move shifter, but after moving the shifter to park the light stays flashing in D4 and the engine turns over but it would not start because in D4 and neutral switch would not let it start. How can this be fixed?

Six cylinder front wheel drive automatic 138,000 miles

Recently my car stalled on a city street. I thought I had run out of gas but that was not the problem because I had at least a quarter tank. I waited a few minutes and tried again, still no response it cranks but will not turn over. Finally it started after about five attempts. I was able to drive about ten miles home and as soon as I pulled in my parking lot it stalled again and repeated the same cycle. I do not know what the exact problem is but I am pretty sure it has something to due with the fuel system. Does anyone have any suggestions?