take it to a mechanic
that's what it is, i have a lumina, had same problem, replaced the intake manifold. run like a top since
start with water pump. If its a V6 3.1L have the intake manifold gasket checked. You may have a coolant leak.
Sounds like a blown headgasket or intake manifold gasket. Sounds like a blow intake gasket to me...It happened to My 86 Mustang and my 96 Lumina.
I'll assume Lower Intake Gasket, since they tend to cause vacuum leaks. Get a manual from Autozone and expect about 4 hrs labor, you need to take off the upper intake manifold just to replace the Lower Intake Gasket. Probably should change/clean the PCV valve while ur in there. Good luck, man.
had a 95 3.1L V6 Lumina that would lose AF as well. Maybe your intake manifold gasket or head gasket are going bad. If there is unusual stuff on the oil fil cap or dipstick you have a gasket leak.
if you had it heat high enough it very likely worped your heads and or damaged the head gasket
if you are going to replace the intake gasket you might as well change the head gaskets at the same time[it will cost you a little now but save you a lot later
Upper intake manifold plenum leak/crack most likely. If its blowing out coolant then you probably have a bad head gasket.
how to change timing cover gasket on a 1996 chevy lumina
You may have the problem of your intake manifold gaskets. They are a problems on the lumina. I had to have mine replaced due to the same thing. Also check if your coolant is mixing with your oil if it is. Than it is definitally your intake manifold gasket.
Try cleaning the intake manifold.
10 ft lbs