The burned valve was the diagnosis from my mechanic, the symptoms are:
a) Very rough idle, a "chug" is felt when throttled up
b) Some loss of power out of the hole
c) a maximum achievable speed of about 36mph.
d) Exhaust manifold on the left side of the engine, is much cooler than the right side.
My diagnosis before taking it to my mechanic was go through all of the normal stuff, fuel filter etc. then I disconnected the plug connector wires while it was at idle. The computer does alarm, (very annoying) but when I reached the cylinder that was not firing, there was no change in the engine idle rpm.
Furthermore, the a "PSSST" sound can be heard from the exhaust on the left side. My mechanic said that he could do a "leak down" test to confirm it, but the labor $$$ would be better spend at removing the head.
Thanks for the compliment on the swim step, I really like the teak finish as well.