Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
Just buy a regular fuel pressure gauge. Harbor Freight has one, but it's not the greatest. An autoparts store is probably your best bet. They may have a loaner you can borrow. You have a fuel pressure port right on the fuel rail to connect it.
First thing I'd check is the coolant temperature sensor. If it's perpetually reading cold, it'll run fine when it is cold, but suck when the engine is actually warm.The truck starts great cold.
Shut it off and let it sit and hr and it starts like crap. Barely fires, sounds like it is about to die honestly.