Hey everybody, been searching the site but this is my first post. I picked up a 2004 silver fx4 ext cab with a 5.4 a few months back.

The previous owner had a timing chain fail. He replaced both chains, cam phasers, and had the heads gone though. During the process of putting it all back together he got sick and had to abandon the project.

Since I acquired it I checked the timing chains (using the timing marks on the cams, flywheel, and chains). I also replaced the plugs and check all connections since the cab was pulled for the rebuild. The truck would eithe turn over but not run or run extremely rough. The fuel pump module looked questionable so I changed it along with draining the fuel tank and purging the old gas out of the system. Still the same problem, usually runs on the first try but rough, eventually does and won't start again. Only engine codes are a p1289, and during diagnostics the "long term fuel bank 1 reads 0%"

Any ideas guys?
Josh T