Did you get the article from http://www.easyautodiagnostics.com?
When you say “…it won’t turn over to start now.” What do you really mean? The engine should turn over (aka cranks up) when the key is moved from ON to START. If the engine does not turn over at all (not cranking) then the starter is not receiving the start signal. That is a different situation.
If the engine cranks but does not start, then I strongly recommend to follow the troubleshooting procedure from http://www.easyautodiagnostics.com.
If your mechanic thinks about the engine being out of time, it could be the distributor was not installed correctly (one or more slots off) or you have some trouble with the timing belt. By the way, did you replaced the timing belt at 105K miles? If not, then a quick cylinder compression test can tell us a lot.
Does the engine cough sounding a piston explosion is happening once in a while?
As I said, I am just getting my van fixed from a crank-no-start condition and extensive troubleshooting pointed at the computer. The computer was fixed and I am awaiting it to arrive home this Friday. However, my van has 237K miles with original distributor by the way.