I say timing, aka timing chain slipped. get you timing light out and have a buddy turn it over. If the light flashes you have spark. if you cant find the timing mark with the light or it way off......time to pull the timing cover.
Doing a compression check is a good idea, but if the timing has jumped the compression will be LOW due to bad valve timing not compression aka ring and valve seal.
just something to think about.
another way to check the timing chain is to remove the #1 spark plug and ground it so it will spark. then us the handle of a screw driver to block the spark plug hole. NOW when you crank it over look at the spark plug Snap and the sound of the air Woosh out of the cylinder............are they happening at the same time? if not you timing change has slipped.
