adeekay

I have a 98 civic ex that i did a whole cooling system overhaul on. Mishimoto aluminum radiator, thermostat, and fans. I put a new waterpump and replaced the temp switch sensor. When i turn off the car and let it cool off for hours the radiator stays under pressure. The hoses stay rock hard and when i take the cap off it starts bubbling and a bunch of pressure escapes making water shoot out everywhere. I did an exhaust leak test and the liquid didnt change color indicating there was no exhaust fumes in my coolant, but i dont how accurate it could be. If its not a head gasket what else could it be? I read online it could be the radiator cap but i checked it and the spring isnt stuck close. I’ve always had heating issues with this car. When i first bought back in oct 2022 the top radiator house exploded on me on the highway and then i found out the heater core neck coming out the firewall was bent, so the hose didnt seal properly and would leak everywhere. It drove fine for a while not overheat it actually drove too cold and then it exploded another coolant hose from the intake and i replaced the hose and now it wont run right. I even took the cap off and let it sit for days without it and when i put cap back on and came back the whole thing was under pressure again.