A few months back I drained all the fluid out of my radiator because I noticed that my car was beginning to run a bit hotter then usual. Then I ran a garden hose through it to clean the radiator out as much as possible before refilling it. So I replugged the radiator and emptied a whole container of fresh coolant into it. The Haynes manual says to use 50/50 but I just went ahead and just used the regular coolant because thats what I had already bought. Then I went ahead and refilled the container with water and added that to the reservoir. Now we're having temperatures down in the low 30s here in Missouri and my cars heater can't seem to warm my car up. It blows out air but the air it blows is just cold. Also my car is once again running at a very high temperature almost in the red zone. I don't know if the car can't keep cool because of a bad radiator or what. It seems that everytime I turn my car off my radiator keeps running for about another minute or so trying to cool my car down. What most likely is the problem with the heaternot heating the car? Possibly a bad heater core?

 

Did you change the thermostat? Completely fill the coolant system back up? Heater core could be clogged especially if you've been using regular water, instead of distilled.

 

No, I didn't know I was supposed to change the thermostat. Well everything that came out of the radiator was stillless then the whole container I added to it in just coolant so I don't see why it wouldn't be enough. I would have unplugged the drains on the bottom of the motor and flushed the whole cooling system out if I knew where they were. So what would you recommend me to do, other then bringing it to a shop to have them flush the whole system out?

 

If your car always runs hot, and rarely cools down while driving, I would suggest changing the thermostat. Its not normally a necessity to replace the thermostat, merely a good idea anytime you change the coolant.

 

Throw the haynes manual in the garbage, or use it to level a table leg, or use it as target practice. but first look to see if it says how much fluid goes into the radiator.
02stangGT is correct when he said the thing about the water. It isnt recommended to use regular water. Distilled is best, it doesnt leave the 'hard water' stuff in the lines that build up.
What do you mean the radiator keeps running after you shut the car off? Are you talking about the electric fans? Do you have an electric water pump?

 

I guess it's the fans that I hear running. And I'm not sure about electric water pump though. I haven't done much work on the car, so I don't know. What should I do other then the idea of spending hundreds of $'s getting the whole system flushed?

 

Try changing the thermostat.

 

Fou can flush it yourself. There are other holes in your mill than the obvious ones. The idea is to get as much clean water in there to push all the yuckie water out. Check for some sonsors the go directly into the engine block, viola there is a new hole to put the hose to. Dont forget to flush out the hoses going to your heater core. Then after everything has been flushed, replace all the stuff that you removed and let all the hose water drain out. Refull the system and purge it, ensure you have the proper capacityand mixture for your car.

 

I'm going to go ahead and change the thermostat. The thermostat is located on the top of the motor correct?

 

I put a new thermostat and gasket in tonight. That fixed the problem because now my heat is hot as hell and my car is running a lot cooler. Thanks to all who offered advice.