92 grand am engine not warming up

i have a 92 grand am 2.3 ohc and when ever i drive for long peroid of time the engine will not heat up to normal range. i disconnected the heater coil because it was leaking antifreeze. does that have to do with the engine not heating up? how do i fix this problem?:banghead: :banghead: :banghead:

change the thermostat with new one.

high or low temp one?

If you live where it gets cold in the winter I would use the 195deg, if you live in the south and dont get realy cold you can use the 180 deg(might be 185).

I live in Indiana and it gets cold!
Though I use the 180 deg thermostat and if it gets super cold I just throw a piece of cardboard over the radiator and it'll get warmer :D