first check your rad is full of coolant.
a blocked pollen filter will resrict the air flow throught the vents. not sure if your car has one??
how far is the temp. gauge going up?????
if its not going half way after driving it for awhile the thermostat may be stuck open or missing causing the engine not to reach proper working temp easy fix.
if the temp. is going half way the little rad. inside the car maybe half blocked, not letting enought hot water throught it. you might be able to flush it if that dont work it will need to be replaced. not a easy fix. hope this works.
petrol head, November 2010