Hot answers tagged

10

This is normal behavior. The A/C system is turned on to dehumidify the air, which causes the windshield to defog. Without it, your breath would freeze on the inside of the windshield and cause further issues. EDIT: Please note Bob Cross' comments below. I found instructions on the Honda Tech Forum which is supposed to give you full manual control over ...


9

You are correct that the only extra energy consumed is the electricity used by the blower fan to move the warmed air. In the grand scheme of things the extra fuel required to generate that electricity is miniscule. The coolant is circulated regardless of the heater setting. Moving the selector to cool or warm merely directs all the air over the heater core ...


9

My top suspect would be a radiator fan that isn't running when it should. The fans assist in transferring heat from the radiator to the surrounding air, and are most needed when the car is stationary. This doesn't mean that the fan is bad. It could be that the relay is malfunctioning or there is a break in the wiring somewhere, so I would try to rule those ...


8

As for the blower only working on max, that screams resistor pack. It's usually in the passenger foot well near the blower motor itself. Sounds like it's held in by two 8mm bolts in your case. Shouldn't be too terrible of a job, but you might want to avoid it if you've got back or neck problems. I usually put the seat back down as far as it will go and ...


8

Here's a nice tip: if you turn up the heat in your car, it helps lower the operating temperature of your engine. Sometimes by as much as 10%. Not a problem when you're driving around in icy cold weather, but if your car is overheating, turning on the heat, opening the windows and putting the blower on full could save your engine from popping a gasket. If ...


7

Check the coolant temperature if you can (if it's an OBD-II car, some readers can give you coolant temperature). If you've got a coolant temp gauge, see if it looks any lower at all (most are pretty hard to read though, one tiny tick down can be a HUGE difference in coolant temperature). I suspect a failed thermostat that's sticking open. I had that ...


5

It takes a long time for the heat gauge to register as anything but cold, about 10-15 minutes. This is almost definitely a stuck open thermostat. The engine should reach operation temperature within 10 minutes, meaning middle of the gauge. You should see it start moving up within about 5 minutes


5

Several Possibilities Low Coolant Level Partially plugged up heater core Partially obstructed heater valve Weak water pump


5

Does your car overheat too? If so, you could have a faulty thermostat, an air pocket in your cooling system or maybe even a leak somewhere. My truck's heat would only work while I was driving, then stopped working altogether while the engine started to overheat. I changed the thermostat, then the heat would blow hot/cold/hot/cold, I didn't realize you had ...


5

It turns out the problem is pretty common with 3.5L Impalas. For some reason these engines lose coolant. Some blame is placed on head gaskets, some blame Dex-Cool. What ever the cause, refilling via the overflow jug can leave an air pocket in the cooling system. The cure is to fill via the pressure cap right to the top. Recheck the level after several heat/...


5

The cheapest way to do so, would be to add something like this aftermarket accessory. Looking for any in-dash options would likely be more expensive.


5

If you mean the rear defrosting wires in your rear window, you should be able to turn it on immediately as it's electrically based. If it's making a noise, I suspect it's the circuit breaker that automatically turns it off based on heat, and you should look into replacing it. What make/model is it? If, alternatively, you have some sort of auxiliary/rear ...


5

If the thermostat is stuck open, you would get the symptoms you describe. A thermostat stuck closed will cause overheating.


4

It looks an awful lot like you have diagnosed all of the really hard problems and come up negative. I wonder if you have a simple mechanical problem: is the linkage sound between the hot / cold selector and the flapper valve that forces air past the heater core. From what I hear, the foam around the flapper is also prone to disintegration in humid climates:...


4

The heat problem sounds like poor coolant circulation, possibly due to low fluid level or partial clogging.


4

It depends on the vehicle, why it is being left, and how it is prepared before being left. If it's a vehicle that's in reasonably regular use, then I'd recommend making sure it's used at least once every week or so, and is driven far enough for the engine to get up to full operating temperature. Just starting it and letting it run is better than nothing (e....


4

Check the overflow tank on the radiator when the car is overheated. If that tank is full, you've probably got a blown headgasket - that's how I spotted mine. For the thermostat; did you buy an OEM one, or after market? Foresters are very particular about the thermostat, and ONLY the OEM ones work reliably.


4

bad air duct door You have multiple air duct doors in your car. One of them will control the air from your heater. You may have situation where the servo motor is bad in a particular door. Sometimes you can have a situation where hot air comes out of one vent and cold air comes from another and various combinations of the issue that maps back to a bad ...


3

You most likely have air trapped in the cooling system. The air needs to be burped out. The method varies by make ,model, year etc. Due to variation between models can you tell us what country the car was made for?


3

Hopefully your mechanic would pressure test the water pump before replacing it to determine if it's really bad. Having no heat is usually a symptom of a stuck open thermostat, but if that was the case, your temp gauge would not indicate hot...maybe a clogged heater core? Did your heater core get flushed? That wouldn't explain the temp gauge reading hot, ...


3

Another option that you could look into is getting an engine block heater fitted. Essentially, you plug those into a wall outlet and they warm up the coolant which both helps with cold starts if you're in a cold climate, and you should get warm air out of the heater fairly quickly compared to a car without a block heater.


3

If the fan is blowing, but no hot air is coming out that means that no hot water is making it into the heater core. I can think of 3 reasons for this, each with a different solution. First, and easiest to check: make sure that there's enough coolant in the car. If it's low, there may not be enough fluid to circulate through the core. Second, the valve ...


3

How cold is it where you are? A lower radiator hose wouldn't do much for you as it doesn't hold very much water and water tends to not change temperature easily.


3

OP Resolved the Issue flow direction was not an issue. OP reconnected hoses and stated the issue is now closed.


3

The reason this occurs is to take care of the humidity in the vehicle while your defroster is running. MANY older vehicles have this as a common function when your defroster comes on. It's odd though that the temperature setting doesn't change your AC temp. Chevy's 2011's were all CAN BUS computer controlled systems, it might just be a glitchy computer issue....


3

As far as I understand it, your pollen filter is filthy and should be cleaned or replaced.


3

If you haven't done this already, check your antifreeze levels of your overflow and radiator when cool. Make sure both are full. Often times, there can be an air lock preventing antifreeze from circulating through the heater core. I normally leave the coolant cap off and jack up the vehicle in the front after starting the vehicle and letting it warm up ...


3

You need to purge your cooling system. Raise the front of the vehicle with a jack or ramps. Driving up a sidewalk works too. With the engine cool (when you touch it it should be cold): Remove the radiator cap. Run the engine. Turn on the heater. Accelerate the engine to 1500-2000RPM. You will see the coolant level go down and/or bubbles. Pour in some new ...


3

I'm in general agreement with Ben. Cooling fan not working. The description of high vehicle speed = okay and low speed not means your fan isn't working for you. This could be a problem with fan controller, fan motor or temp sender used to turn on fan. Note, the fan shrouds matter big! Ensure they are sealed off to radiator correctly. Please check the ...


3

I would check the water pump, it sounds like the blades may have corroded away. From your description it certainly sounds like the water isn't circulating.



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