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  • Heater Cores and Blower Fans
  • Car Heaters

Why would your car heater overheat?

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βˆ™ 2008-03-10 00:56:01

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I have a 1992 Plymouth Sundance with 130000 miles. 4 cyl, 2.0L It has been well taken care of with regular maintenance between 3k to 5k intervals since I bought it with 58k. The car instantly overheats when turned on. The heat blows frigidly cold air. It has a thermostat that is ~5 months old. The car will shudder and shake and then cut out when left idling or when it over heats. It is not losing coolant, but the car smells like burning antifreeze when you lift the hood. It will also steam and or smoke that escapes from under the hood when you turn it on. 1.) What are the possible diagnoses? 2.) How much will it cost? (Chicago area) 3.) Is it worth spending the money on a rebuilt car that I've had since high school, or should I just give up and buy a newer car? The most common cause of simultaneous engine overheating and no heat from the heater is extremely low engine coolant level, in other words a large pocket of air in the system. In some cars it's fairly easy to get the air out, in others it's very tricky. If there's a leak causing coolant loss, that will also have to be addressed or the problem will recur/worsen. Check 1. Your Thermostat (70%) of the time it is your thermostat. 2. Check and see if your radiator is clogged (Also very common).

Another issue is if your car overheats during idle, then it could be the electric radiator fan.

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2008-03-10 00:56:01
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Related Questions

Will a leaking heater core cause your car to overheat?

A leaking heater core will cause the engine to overheat because the coolant is leaking out.

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No, a clogged heater core will not make it overheat. A leaking heater core will.

What would make a car overheat?

Try changing the themometer

Why does car over heat and water fog up windshield And the smell of antifreeze stong in car?

Typical of the heater core leaking. Overheat because of low fluid and pressure. Foggy windshield due to heater core leaking and will smell antifreeze in the car.

Would the fuse in the heater relay cause the heater to leak into the car?


Why would a car overheat in the winter?

thermostats problem my car did the same thing when mine went out

What causes a 1997 Honda Civic to overheat if the heater is not on?

generally if an engine overheats, but then does not overheat when heater is turned on, is a good indication that the engine thermostat is stuck and needs replacing

If Heater core is bad on a 1984 Mazda GLC will car overheat?

Not necessarily. It depends on what you mean by a bad heater core. The core will either be leaking or stopped up. If it is leaking, then it can cause the engine to overheat and the only fix is to replace it. A clogged or plugged heater core can sometimes be fixed by flushing it. You can also temporarily bypass the heater core until you can get it fixed. Just connect the inlet & outlet heater hoses together.

Why would my car overheat but the heater blows cold air?

You should check your water level. It's low, and you have a leak. Get someone to check it for you. The heater in your car works off the water from your radiator, no water in the radiator will over heat the engine ergo top up the water. Could also be low antifreeze level causing water in radiator to freeze making the engine overheat and the heater to blow cold air. You have an airlock. If you have a system with expansion/filler tank then check the return pipe is not blocked. These systems bleed themselves if there are no blockages. Mine was because the impeller in the water pump had disintegrated to the point where it would not move the water. The water would overheat, but the hot water would not get moved into the heater core to blow hot air. I replaced the water pump and it all works now.

Car starts to overheat when idling and heater does not blow hot air radiator fan does not kick on when car heats up what could be the problem?

either the thermostat or the fan is no good. You would need to locate the thermostat and see if its stuck open or closed!

Can you drive a car home when the heater core is out?

you would have to bypass the heater core first.

Why would smoke come out of the ac vent?

smoke coming from a/c vent indicates that the heater core is leaking and needs to be replaced.this smoke is hot antifreeze, it will not cause a fire but it does stink and will eventually cause car to overheat

Will a car overheat in the winter?

no, it will not

Would a car overheat if left in park with the AC on?

It can if their is something wrong with the cooling system.

Why would the alternator over heat the car?

It will not cause the engine to overheat. You have another problem.

How do you know your heater core is leaking?

Usually, you'll get antifreeze on your passenger floor, steam out the defrost and / or have a very noticeable sweet coolant smell in the car. The heat won't work well and the car will overheat.

Will a cracked head gasket on a 1996 Subaru Legacy L 2.2L cause the car to overheat and the heater to blow out cold air also?

the blown head gasket would make it over heat. but it wouldn't cause the heater to blow cold, it should actually blow hot if that is wat happened

What would cause a car to overheat when idling?

The radiator cooling fan is most likely not working.

Can a 266 volt heater be wired to 480 volt circuit?

No, it would overheat, might blow the fuse, otherwise it might catch fire.

Does the ac cause the car to overheat?


Can a car overheat with a stuck open thermostat?

Usually the car would run cool, unless the thermostat is stuck partially open.

Would bad heater core cause car to sputter?


Is it safe to drive a car when the coolant tube is leaking inside?

No , this coolant is coming from your heater core and you are losing engine coolant ; you need to have this repaired because the engine will overheat and suffer damage that will be more expensive than the repair of the heater core .