Been struggling to get my 1988 Oldsmobile Cutlass Supreme SL working for quite some time. I've solved several issues in it but now I'm really stuck. When running the car as soon as the coolant temp gets to around 203-207F the engine will cut out. If I bypass the primary cooling fan relay and cool the engine down below that, it will start, if I don't cool it first it won't start again after dieing. When I let it cool down and then start it again it will do the same, run fine, then once it gets to that temp range cut out. I've checked both primary and secondary fans they work fine when I bypass the relays and the relays checked out on a powersupply and fluke test. Neither me nor my dad have any idea what could cause this issue at this point so I was hoping I could tap into everyone's knowledge on here. Any help would be appreciated. We've replaced a lot of stuff on this car so I'll try to list what's new.

ECU, TPS, Purge Cannister Control Valve, Fuel Pump, MAP/MAF, EGR, Spark plugs and spark plug wires, O2 Sensor, Ignition Coils, primary cooling fan, and fuel filter.