96 Grand Am 3100

I'm having a problem, was losing coolant, and now it is in oil. How do I differentiate if it is a head gasket or the lower intake manifold gasket failure this engine is (in)famous for? Thank you.

Do you have steam coming from the exhaust? This is a sure sign of a blown head gasket. You can also pull the plugs and look at them, if there is coolant in the cylinders you should see some evidence on the plugs. A compression test will also indicate if there is a problem. With this particular engine the manifold gasket is where I would start especially if there is water in the oil.

No steam from exhaust, not ever overheated, will check plugs today. Thanks for the input.

Update, it was the intake manifold gasket which had blown. No water in cylinders, and not too bad a fix either, will finish buttoning it up today. Thanks.