Nitrider73

Hey guys Im new on here and I really hope you guys can help me out. Heres my problem I bought a 93 prelude si 4ws auto tranny with a h23a1 bought it with bad main bearings so I had the motor completely rebuilt with new pistons, all new gaskets, the mains on the crank turned .20 over and had the head shaved .40, 5 angle valve job. Well Heres my problems If I drive over 50 mph It will tend to start to overheat slowly, only one of my fans kick on, but if i stay under 50 mph and have the heat on full blast it will run normal temp. Is this because I have had my head shaved so far down? Im pretty sure I bled all of the air out of the system. How can I keep my engine cool? 4 core radiator? Or coolant additives? Also I have another problem If I get up to the speed of 55 mph or faster my check engine light will come on, but when I shut off my car the code disappears. Could this be a O2 sensor? One last question Where do I check my error codes on my car with it being an OBD1 I know you have to use the paperclip and count the codes But where is it located? Is it the same plug in that I check my 4ws codes? Guys I have had alot of tuners in my life But so far this is one of my favorites so far and I dont want to get rid of it, so can you please help me out? I would be in a debt of gratitude to you guys.