My 4 high won't work but my 4 low will, now when I go back to 2wd my 4wd service light is still on with the truck not being on 4wd anymore? Thanks for your help

I put gas inside throttle but still won't start

a garage told me i had a vacuum leak,it idles high.i put it on a computer,the code read continus misfire ,i put new plugs &wires on still same reading.where are all the vacuum lines i need to check?

Anytime we try to crank it the starter just clicks nothing else. The battery doesn't stay on long either. We already know the fuel pump needs to be replaced. Would like to know more suggestions.

What could be causing the problem

I have about 277,000 miles on 2nd motor, replaced everything so far except transmission.

intermitting fuel delivery

wants to start and still won't

when it does blow it works on all speeds

the bulbd are good