A.Adjust the Valves.
B.Check the Timing Chain "Stretch" (Wear,It Wears).
[Replace it + Sprockets if out of Specs.]
C.Check the Timing.
D."Pop Test" your Injectors.
E.Injectors are out, may as well Compression Test ,Too.
1. Find and clean out your Banjo bolt(AND all lines to + from it)
(Might as well clean the entire Intake system,Too.)
2.New Fuel Filters: Primary (Small Inline one)Secondary (Spin-On) and the Tank Strainer underneath the Fuel Tank.
3.Startron in the Tank.
http://mystarbrite.com/startron//content/view/16/39/lang,en/
4.Diesel Purge (Lubro Moly)
5.Italian Tuneup
Report back with your Happy results.
How lucky do you feel,Stranger? Just try #1.