Starting problem
 

Have 1987 F150, 4.9 6 cyl fuel injection, truck starts and runs ok until , I shut off, it will turn over but wont start, if I wait 20-30 mins it will start, can anyone help, had it to a garage, getting fuel pressure and spark, they did change the coil as the coil was the original, only have 138,000 on odometer, Can anyone help?

My '92 with 4.9 had the same problem. It was a weak fuel pump. Check the fuel pressure with the engine not running and key on, it should be at least 45 psi immediately after turning the key on. Check while idling, it should be at least 42 psi, disconnect the vacuum line to the Fuel Pressure Regulator (FPR) and it should rise to 52+ psi. .

Could also be the pick-up coil in the distributor.

Mechanic did suggest replacing complete distributor, not sure if that will solve problem as truck will run , until I shut off, and others have done this and it still didn't solve the problem, and the 500 - 600 buck expense, and on previous post regarding fuel pump, I did have in garage last year as fuel pump wasn't working, so he wired it direct so that when turn key pump comes on,

I would look at the fuel pump, fuel filter, fuel pressure regulator, and fuel injectors.

Fuel filters
 

Thanks, will look at

When it won't start, just shoot a little starting fluid in the TB while cranking. If it starts, your problem is fuel delivery. If not, it is spark.