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I’m having an issue with my car thermostat. Temp gauge goes up slowly after driving. I’ve replaced lower radiator hose, a heater hose, thermostat, water pump and timing belt kit, i also had to bypass my electric fan to get it to stay on. Any help is appreciated.. idk if it maybe the fact I got an oem thermostat with the half sized radiator or what it is. No leaks, just gauge goes up. No chocolate milk either. Thanks guys