I have a 96 Ford Taurus and recently I have had trouble getting it to start. I have always had to turn the key back and forth in the ignition a couple times before I tried starting it to actually get it to start. Now that won't work. I have replaced the battery and starter and nothing seems to work. All the electronics work and it does "try" to start. When I tap on the gas I can hear it trying to fire up. But to no avail. Any suggestions? Thanks for any positive input.