fi= fuel injection
Its on my 92 4cyl rodeo, 2600cc, w/ fan/clutch fan cooling.
the truck used to overheat while at idel or in traffic, usually after 45min of use on any condition of driving. With new h20 pump, and stat.
Well its been sitting for over 2yrs now, I thought it maybe a bad head gasket or even a cracked head.
Today I started it, fixed a bunch of vac leaks, and put Redline water wetter in it. let it idle for 1hr45min, and no boil-over like before. ( I know water wetter isnt that good).
I am going to pul the head off this week and get it all chked out too.
I WAS JUST OVER THINKING, and thought that unmetered air would cause, overheating due to unequal amounts of fuel not being added to the combustion chamer. ( I over thought the entire thing), it got tto be a bad gaset or head, but there are no signs of them being bad.

BTW, I was on the 97 NCSU A&T Baja SAE team.