Car is blowing cold air from heater and engine is getting hot?

Question

It is a 1989 Lincoln continental, it was really low on coolant I added coolant then started car and turned heater on so that i could add more but, did not seem to need much more. Took it for a drive and engine started heating up and heater blows cold air. Any suggestion?

Answer 1

Same thing happened to me in a Taurus. It turned out that there was a bubble of air trapped somewhere in the cooling system and that was sort of "vapor locking" the flow of coolant. No flow, no cooling, so for years the engine would frequently overheat, but no flow also means nothing going to the heater core so the air blowing through that stayed cold. I had a pressure flush on the coolant which removed the air bubble and I haven't had the problem for 3 years now. One other possibility -- if your antifreeze/water mixture isn't where it should be, you can get a bit of ice that can block the flow of coolant and produce the same symptoms. That melts fairly quickly though and things will very suddenly go back to normal (until the next really cold day).

Answer 2

Providing the heater was working ok previous to the coolant level going low there is a strong possibility you have an air lock in the system and therefore no coolant circulation through the heater core. Also pay attention to the coolant shut of valve . These only pertain providing the thermostat is ok. With a bad thermostat you should at least get a little heat. Bob

Answer 3

Unfortunately, I have some bad news for you. You probably have a blown head gasket. The outflow from the cylinder that has the problem stops all water circulation. See if the circulation starts again if the radiator cap is removed. This will vent combustion gases and allow normal flow. So if you run the engine with the cap off, and heater function returns, and then you put the cap back on and the heater function quits, you almost certainly have a blown head gasket. To confirm this, call around to some of your local garages. Tell them you suspect a head gasket leak and want to know if they have a chemical tester. If they do, take the car down to them and to have them run the test (shouldn't cost too much, and it only takes 5 minutes.) They place a glass tube with a rubber seal over your radiator tank opening or your expansion tank opening, put in some test fluid, and use a rubber bulb to suck air through the test fluid. If the fluid changes color, it means there ARE combustion gases in your cooling water, which indicates a blown head gasket. What do you do then? Well, the first step would be to try one of the head-gasket-sealers-in-a-can that the auto parts stores sell. This is the cheapest for a first attempt. Will probably run you $10 to $70 depending on which magic sealer you use. If this works, you are good to go. If it doesn't, the next step will be a head gasket change.

Answer 4

Your heater core may be blocked. If flushing the system doesn't do the trick, then you'll have to replace it.

edited to add: I'm thinking zebras instead of horses. The thermostat is a very good first step. Try that first.

Answer 5

When you say the engine is getting hot, do you mean hot as in running hot, or hot as in reaching operating temperature? If the engine is running hot I would say change the thermostat. If it is not running hot then the valve that controls the water to the heater coil is not opening.

Answer 6

have ur system flushed out,ur thermostat change or check,refilll with coolant..or ur heater core is bad and needs to be replaced..good luck tc.

Answer 7

change the thermostat and flush raid. add new coolant to fix,,

Answer 8

Have the thermostat checked.

Answer 9

.Your thermostat is bad. This is a a minor repair job, and if you are mechanically inclined you can fix it yourself

Answer 10

bad thermostat.