Thought. Test drive with fuel cap removed.
I've had the issue ever since the Titan tank was installed.
The 0087 is getting very bad!! Just pulled a 6000lb camper to salt lake city. Threw the code on just about every hill. Brand new fuel filter at the start of this trip. Just gonna drop it at the dealer Monday. It was almost undriveable, threw the code as much as 5 times on a hill.
The fill up issue started after the tank install.You stated this started right after the titan tank install, correct?
Sounds like you have greater problems than before. If there is a supply issue throw a lift pump on that thing. This will help a week cp3 on drawing fuel to the pump @ low psi. If the cp3 is weak on the high psi side than that is another story.
High fuel psi codes now? Have you used your dvt tool and ramped up and down rail psi and logged the info?