i just changed my coolant. its sitting above the full line in the resvior. my engine heats a lot faster than i think it should but stays right between the hot and cold on the thermostat. then it takes a lot longer for it to cool down. could this be because of the wrong mixture or the wrong kind of antifreeze (i put in pride antifreeze and coolant.)? i didnt do exactly 50/50 because some water spilled out. should i add a little more water? Thanks for the help.