Switched my starter, crank position sensor, alternator, battery and my truck will not turn over. Sounds like it wants to start but won't. Only way it does is if I spray starting fluid.

 

Truck idle's very low a we'll.

 

OK. So it wont turn over, but sounds like it wants to start then does start with starting fluid but idles very low? I can't really tell what your asking. Could be a fuel pressure issue.

 

Offer it a treat, and ask nicely: "Roll over, there's a good boy."

Oh wait.....

Ok, cranks but won't start, and if you spray, it makes the appropriate noises.... Put a fuel pressure gauge on it, and see what it has to say.