As Roy suggested, definitely check the pump's output and the catalytic converter. The aftermarket pumps for these trucks are somewhat bad and often do not put out the pressure that they are supposed to. My aftermarket pump quit working, and the warranty replacement requires priming before I start it sometimes. You can borrow a fuel pressure tester from AutoZone and run the test for it. It should get something like 59 psi with the key turned on, engine off. As for the catalytic converter, the simplest way to check that is to take the upstream O2 sensors out and see how it does. It will be loud as heck though, so do not do it when the neighbors are asleep unless you really do not like them.
Wednesday, January 17th, 2018 AT 7:15 PM