Engine Mechanical problem
1992 Ford F150 6 cyl Four Wheel Drive Automatic 160000 miles

My truck is a secondary vehicle and I seldom drive it.
Well before driving it today I check all the fluids and coolant level in the radiator. Well it was a little low so I topped it off. Well like and idiot I did not put the cap back on and I drove off. It overheated. I got it cooled off and replaced the coolant. I drove it back home some 30 plus miles and it did not overheat again. The problem now is that it is missing pretty good especially when it is idling. Other than that the engine does not seem to be in any distress such as knocking or pinging.
what could be the problem