How do you replace a heater core on a 1991 Olds Cutlass Supreme 31 V6?
its very simple man its located under the dash in a black box. its right under the controls where the ac is. make sure u take the positive battery cable off before working on it. the hardest part is finding it once u do is easy from there. just take out the other and put the new one in. it is recommended that u should flush out your system but its not really nessacary.