99 Ford Escort (Tracer) starting issues CEL

OK... My friend has a 99 Tracer and she says it has been "sputtering" while driving. She took it to the stealership the other day and they ran a diagnostic. They gave her the codes PO455 (evaporative emission control system, pressure sensor intermittent) and PO733 (incorrect gear ratio, 3rd gear) They told her that the 455 code dould sometime trigger the 733?? Anyway, they proceeded to tight the gas cap to see if that would work and sent her on her way. Well, her car died last night and now it won't start. I tired changing the spark plugs and a new air filter today because they were long overdue, but it didn't work. The engine was turning over pretty good before I started fooling with it. The starter sounds more like it is grinding now after I changed the plugs. Does anyone have an Idea what the problem could be? Any help eould be greatly appreciated.

There are several things to check but did you check the timing belt. It sounds like it may have broken causing the engine to stop running. You can check this by removing the oil cap and looking at the valves while the engine is turned by the starter. If you see no movement then the timing belt is broken and needs replaced. That may be why you are hearing strange noises.

Check the fuel cut-off switch.