Ive had my truck for over a year. Back in January of this year the lift pump went out. I replaced it with an airdog. No problems until recently. It started not wanting to fire after it had reached temperature. The scanner at the dealer showed it was getting only 30% of fuel delivery to the rail. Maybe the sensor is messed up. Because it will fire up when cold or left alone for a few days. Has anybody had the same problem?

 

It's either the CP3 is bad or the rail pressure sensor is bad. Replace the simple stuff first, like the fuel filters.

Are you getting fuel to the CP3? Do you have a fuel pressure gauge?