Hi Caytlyn,
I don't know if you've gotten this taken care of yet, but if not, here's a few thoughts.
First is - are you actually losing coolant somewhere? Is it dripping on the ground when parked, is the radiator/recovery tank low, do you smell the sweet syrupy smell of coolant around the front of the car, or in my case, actually seeing steam rising from the radiator area?
Second, if you want to see if the thermostat is opening up, when the engine is warmed up (or indicating that it's getting hot), feel the upper radiator hose. If the thermostat has opened, that hose will be very warm. If it feels cold or just the same as the outside air, it could mean the thermostat is stuck.
Third, a common cause of both overheating and loss of heat inside the car is air trapped in the cooling system. This can happen from losing coolant, or from adding coolant and having air get trapped inside. It's possible that the air pocket is right at the thermostat, stopping any coolant from touching the coolant temperature sensor - basically the sensor is reading 'hot air' and may have the gauge show a hot reading when it may not really be hot. This air pocket can spell trouble for cylinder heads and other engine parts because they're not being cooled properly.
A way to release this air is to open the bleeders in the system to let it out, and get the cooling system filled completely with only coolant. If you follow the upper radiator hose to where it joins the metal thermostat housing, you'll see a small brass screw with a hex nut head on it. It's a 7mm nut, and made of brass, so it's rather soft - don't use much force to loosen or tighten it or you'll strip it. Loosen it to the left about 2 full turns (with the engine off and cooled down). You don't need to take the screw all the way out - air will escape by it when you loosen it - you may hear it come out.
Now, follow the lower radiator hose on the left to where it connects behind the water pump. There is a black metal pipe sticking up there and on top of it is the 2nd bleeder screw. Open that one as well.
With those both open and the radiator cap off so you can fill it, the idea is to keep adding coolant until you see it dribble out of both bleeder screws. That will mean you have all the air out and nothing but coolant is in there. Then, tighten the two bleeder screws back up (carefully), put the radiator cap back on, and fill the recovery tank to the cold line.
Now, drive it, let it warm up, watch the gauge, and see if you have heat now.
Upper radiator hose/Thermostat housing bleeder screw:
Water pump housing bleeder screw:
As for the blown head gasket - one way to check for either a blown head gasket or a blown lower intake manifold gasket (which these engines were infamous for) is to look at your oil. Remove the oil filler cap, and look at the bottom of it. Shine a flash light into the hole where it was in the valve cover and look at the oil on the dipstick. It should look like honey if freshly changed, or dark brown if you're in need of an oil change. But, if you see any thick butterscotch or chocolate pudding looking stuff anywhere, you more than likely have one or the other (or both) gaskets blown and coolant (Dex-Cool) has mixed into the oil and gotten whipped up by the moving parts inside. This is not good, and what happened to my WolfTek.
Hope this helps some
Mike
