Heater blowing cold air?

The heater does not blow warm air at any temp. The thermostat is new still no heat. When the heater is turned on and driving car temp goes up to around 200 as soon as turn off or flip to a/c it cools down so that tells me thermostat is working properly. The heater hose on the front side of motor gets red hot to the touch however, the rear hose next to the firewall side stays cold. The front line was bled of air very little came out. Is there a valve that I can adjust to open it up to flow warm water thru heater core? Is the hose stopped up? Is it the heater core? Help me please it is getting cold here in the mornings now. Thanks !

That engine was prone to clogging the heater core from oil getting in the cooling system or the coolant (dex-cool) sludging up from either mixing with regular ethylene-glycol coolant or neglect.
Check the overflow tank (engine cool) for a brown or black sludge in the tank.
Secondly, make sure that you are opening the bleeder valves when you are adding coolant or air pockets will form and the heater will not work.
Finally, pull the hoses off the heater core and put a garden hose on one of the heater nipples. Turn on the hose and watch for water to come out the other nipple.
If no water comes out the other nipple after about 15 seconds it will be necessary to replace the core.

I have a 1998 chev. Malibu and I have no heat. I change my themostat, my heating coil, and my water pump, what else could be wrong.

The hose was change when the heating coil was change.

The hose is now getting hot, but cooler air is still blowing in the car, and I just notice that the value cover has water coming in it, never saw this happen before.

My heater starting making strange noises this week. On settings 4-5 it would blow regular then slow down and this would happen the whole time I was driving going high then low, as if it would turn off. Today it takes time to go on and then does not go full force, barley blows at all and at level 1-2 it shuts off. Can this be the heater(motor) blower resister? I've heard that this is a defect in 1997 Malibu's!

Heater problem
1997 Chevy Malibu

My car heater has recently started blowing cold air instead of hot when the heat is on. When this happens I noticed my temperature gauge rises faster than normal when the heat does kick on ( sometimes It does) the gauge drops to the right level. Is this my heater core or my thermostat? How much will this run me?

Is the coolant low by chance? Sometimes the coolant system can get air bound resulting in no heat and irractic temp gauge. Let me know.

I'll check that and let you know! Thank you!