i have a 1986 f150 haveing trouble with starting....if u hold the key to the start and fether the gas it will keep runing but if u turn the key loose then it will stop....while holding the key to the start haveing someone pull the small wire off the sol....on the fenerd then it will keep runing till u turn it off.i would be greatful for any help with this

 

From what you describe, the ignition switch on the steering column under the dash is faulty .