I have a 2003 f150 supercrew with 17,686 original miles I have a slight miss at park idle

 

Throw a couple bottles of Techron in a fresh tank of gas and take it out for a good hard run.

 

the truck have been sitting in the garage for 15 years , it was a no start I drop the tank and the fuel pump and everything that wasn’t metal on it has turn to gel .. do you think the fuel injectors are bad now

 

Try what glc said. Techron may clean up the injectors. It's good stuff.

 

Flush the gas tank out, clean the fuel pump and strainer, replace the fuel filter, fill it up with a good quality top tier name brand gasoline, and put in double the recommended dose of Techron.

Now - that only takes care of the fuel situation. I think I'd change every fluid in the truck. Oil, filter, trans fluid, power steering fluid, brake fluid, coolant, differential fluid.