Vehicle is a 1999 expedition 5.4L, on occasion the vehicle won't start, it wont even turn over. I have to pop the hood and jump the starter relay on the fire wall and then it runs. I had the starter checked and it was good, the starter relay on the fire wall is also new and I also replaced the battery cable harness. I'm thinking its the ignition switch but not 100% sure. Any ideas?

 

Do you have slop in the shifter ? You may have an issue with not going into park properly . The neutral safety switch may be faulty also . Just a few thoughts ...

 

If that's the case I should be able to put it in neutral when it doesn't start to start the vehicle?

 

Possible . Try neutral and such . Look at the base of the column where the shift cable attaches , see if that bit is loose .

 

Check for a sloppy shifter lever first. There's a pair of screws under there that loosen up and cause your issue.

 

Yes, or another method is (with your foot on the brake) to reach over with your left hand and hold the key in the start position while moving the shifter down with your right hand until you hear the starter engage.

 

The neutral safety switch is new, the transmission was just rebuild. The two torx screws are tight and this shifter doesn't have any slope in it.

 

Check fuse F21 with a test lamp with the keyswitch in START. That fuse should go hot in that switch position.

F21 is in the circuit that includes the DTR switch between the ignition switch and the starter relay under the hood.

 

In that case you could be looking at a worn ignition switch, just as you suspected earlier.