Cranks with spark and fuel, no start

Pulled this one out of the bushes. When I first put a battery on it she fired right up and with some ground cleaning and whatnot idled nice on its own.
Drove it about seven miles home through town with no issues. Put a bottle of fuel treatment in and idled her through about quarter tank in the week it has been in my driveway. Idled rough a couple times. I did notice some steam/water coming out of the exhaust.

Today hopped in to turn it around and it fired right up and purred. Backed around and turned it 180° and it just quit running. When you try it cranks strong but wont run.

I replaced the air and fuel filters. I am getting fuel out of the pump. Out of the filter. And pressure when I push the schrader.

I get spark directly out of the coil and out of plug wires. Plugs look newer and fine.

Doesn't sound like timing belt, as it tunes over. Doesn't sound like cam sensor, since there is spark. Not the fuel. Ignition module fail wouldn't send power to starter.

Would a coolant temperature sensor cause it to crank and fuel and spark but just not run?

Any ideas? Should I just relentlessly scour for a loose wire somewhere?