this should help you....from what you are saying,,it sounds as if you may need to pull the distributer and re-time it...
you need to take out the #1 plug,,,hold your finger on the plug hole...have your help to bump the starter till you feel air[compression]start to come out of the hole....then hand turn the engine until the mark on the harmonic balancer is on [o]..now you have the #1 piston up on the compression stroke...now,install the distributer to where the rotor is pointing to the #1 plug wire terminal...now it is in time
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FIG : Fig. 4: 2.8L engine . Firing order: 1-2-3-4-5-6 . Distributor rotation: clockwise