overheating about 10or 15 minutes into driving ,losing coolant , check engine li

What is your question?

I have repaired the intake manifold gasket and put a new thermostat in it.there is no water in my oil .i have a broken mode door actuator and a exhaust leak

What makes this problem better or worse?

Heater On high and on it on temp hot

How long has your 2003 Oldsmobile Alero had this problem?

A few months