My car running hot in blows cold air out of blower already replace thermostat and radiator relay switch for the fan

How hot is the engine running in degrees f? Does the radiator fan run?
With hvac turned on, check voltage and ground at the blower motor. If good voltage and ground, suspect the blower motor is faulty.

There are other things to test before we have the engine spread all over the yard. Cooling fan operation. Yes the thermostat hot air in heater just means hot water. start with a cold engine then start and run at a high idle if heats quickly upper radiator hose hot lower cold good but reverse no flow. remove and test thermostat (not replace) put on stove boil water and watch it open once center piece is moving check with thermometer it should agree with stamp number on thermostat. if good check for slipping fan belt. check for air restrictions on radiator and water flow.

There is a separate heater core, like a small radiator, which needs hot water running through it, so when the air blows over it, the air gets hot. It sounds like the diverter valve which sends the hot water to this heater core is not working. It could be a problem with the valve itself, or the relay or switch that controls it, or the vacuum line or device that opens the valve when the switch or relay tells it to open.

Sounds like your cooling fans on the radiator are not working. The fans are activated by a thermol switch on the engine or radiator reading the coolant temperature and an A/C switch. When the coolant is too hot the fans should activate cooling the system down. And, when the A/C is on the fans should also activate in order to cool the condensate so the A/C would work.

When you are driving, the movement of the vehicle throught he air is providing enough air flow to keep things cool and functional.

I would check the radiator fan fuse or fuses first. If those are OK I would try to run the fans with 12 volts and a ground that I supply just to see if the fan motor(s) actually run when powered. If the fan don't run when powered then the fans are bad and will need to be replaced. If the fans do run when you power them manually, then something is not allowing the power to activate, like a relay, control unit, or wiring.

It will take a little diagnostics, but it is not too difficult to chase it down.

REPLACE THERMOSTAT.MAKE SURE COOLANT SUPPLY PIPE OR COOLANT RETURN PIPE NOT STOPPED UP AND YOU HAVE ENOUGH COOLANT IN THE SYSTEM.REPLACE THERMOSTAT.CRANK ENGINE UP AND LET IDLE UNTIL WARM UP KEEP EYES ON TEMPERATURE GAUGE. WHEN ENGINE THERMOSTAT OPEN COOLANT HOSE SHOULD BE HOT.IF NOT TURN OFF ENGINE.USE LARGE RAG WAIT A WHILE BEFORE REMOVING RADIATOR CAP CHECK TO SEE IF COOLANT LEVEL DROPPING IF SO ADD MORE COOLANT.CRANK ENGINE UP UNTIL THERMOSTAT OPENS UP.HOSE WILL GET HOT.IF STILL COLD CHECK COOLANT LEVEL.ONCE YOU AIR OUT COOLANT SYSTEM RADIATOR HOSES WILL GET HOT SO YOU WILL GET HEAT.IF COOLANT LOW YOU WONT GET NO HEAT.

It seems to Me that, the heatercore is not functioning properly. Its just like a radiator, the hot water runs through the core, once the thermostat opens at it's set temperature and having the blower motor on, it should blow out hot air.

Take off your radiator cap when it is cold. Start your engine and look inside the radiator and see if the water is circulating when it gets warm. Rev the engine while watching inside the radiator hole. Be sure to be careful to not get burnt by letting it get to hot. You just want to see if the water is going around. If it is not, you could have a bad water pump.

your electric cooling fan is not switching on that is either 1. you fan is bad which you can test jumping a hot wire to the pos side of the fan if it works then exclude it. 2. your fan works on a ground system there is a coolant fan switch in the head that can cause no fans, and the last 3. nfan relay or fuse bad

Either Your fan switch is burned out or you blower motor is no good, your blower motor is on the passenger side under the dash. Before you replace any parts you need to check your fuses and relays under your hood and in the car. Usually if your fan switch goes bad you will still get some air blowing thru the vents, so my guess would be blower motor, If its not a blown fuse or relay.

Radiator Fan Control Relay Switch. I bet your electric fan doesn't run?