Okay - so we tinkered further. Bought a new coil and there's healthy spark so we can eliminate the resistor as the problem. Also re-tested the compression for each of the four cylinders, here were the results of the highest compression both before and after I added a dab of oil: 55 to 75; 60 to 80; 60 to 90, 60 to 100.

We also ruled out that there is a draw on the battery.

In chatting through this with my neighbor, who is actually a car guy, our hypothesis is now that the engine is tired. In other words, do you think the fix here is a new engine block? If so, that's too bad because it likely means I bought a lemon (only bought this last July).

If not any other ideas for what we could eliminate/test for? She's a beaut, but I don't have the time, skills or knowledge for a full engine replace.