Vehicle won't start

You have a timing chain in this engine. Chances are it isn't the problem. You need to check for spark and fuel to the engine. If you have both, and the spark is a hot blue spark, then see if the engine will start with starting fluid. If it does, it is a fuel related issue. If it isn't, then you need to check the timing, compression. I have no idea how many miles are on the engine. Are you sure it is a 2.8L? I believe they stopped using that engine in the early 90's and went to the 4.3L.