I've been noticing some issues with my wife's Corolla recently. It's been taking about 10-15 minutes to heat up which I didn't think much about until today. The car had been running for about 20 minutes without any heat when the temperature gauge started to fluctuate between overheating and normal. All the while no heat comes out when the heater is on. Just cold air. In addition, my wife describes hearing what sounded like a lot of running water "like the tide came in," as she stopped at an intersection. She didn't see anything pouring out behind her car as she pulled away. I have no idea what this could be. My neighbor seams to think it is the heater coil. I'd like to see what you all think before I dump that much money into it. Thanks for any help you can give!
97 Corolla Heating Issue
- Thread starter filmering
- Start date
Welcome to the Corolla Forum! 
I hope you hang around for a while.
By what you describe, guessing of course as there's no way to diagnose a vehicle problem over the Internet, by your description it sounds like the anti-freeze/coolant is low. Look at the overflow tank in the engine bay and see if the anti-freeze/coolant is below the full mark, or even lower. If it is, this indicates a cooling system leak somewhere that a professional automotive technician will need to diagnose.
With the anti-freeze/coolant being low, it's not wise to drive the car in this condition as it can overheat causing serious and expensive engine damage. By what you describe, it sounds like the anti-freeze/coolant level is so low that it isn't reaching the heater core to provide heat in the interior of the car and after the engine has run for a while, with the level being low this can cause the anti-freeze/coolant to overheat and start to boil, which makes it expand and register on the temperature gauge. The sound of water running is probably the anti-freeze/coolant boiling and moving around inside the cooling system. If this is the case, you are very fortunate something in the cooling system didn't blow, like a radiator hose and lose all the anti-freeze/coolant.
When the engine is cold, (so as to avoid having steam blow up in your face and scald you when removing the overflow tank capl),top off the overflow tank with the proper antifreeze type, (any competent auto parts store can provide you with the correct product), and get it to a competent automotive technician for proper diagnosis before an engine worth thousands of dollars is destroyed.
I hope this is of help. Let us know how you make out. :thumbsup:
I hope you hang around for a while.By what you describe, guessing of course as there's no way to diagnose a vehicle problem over the Internet, by your description it sounds like the anti-freeze/coolant is low. Look at the overflow tank in the engine bay and see if the anti-freeze/coolant is below the full mark, or even lower. If it is, this indicates a cooling system leak somewhere that a professional automotive technician will need to diagnose.
With the anti-freeze/coolant being low, it's not wise to drive the car in this condition as it can overheat causing serious and expensive engine damage. By what you describe, it sounds like the anti-freeze/coolant level is so low that it isn't reaching the heater core to provide heat in the interior of the car and after the engine has run for a while, with the level being low this can cause the anti-freeze/coolant to overheat and start to boil, which makes it expand and register on the temperature gauge. The sound of water running is probably the anti-freeze/coolant boiling and moving around inside the cooling system. If this is the case, you are very fortunate something in the cooling system didn't blow, like a radiator hose and lose all the anti-freeze/coolant.
When the engine is cold, (so as to avoid having steam blow up in your face and scald you when removing the overflow tank capl),top off the overflow tank with the proper antifreeze type, (any competent auto parts store can provide you with the correct product), and get it to a competent automotive technician for proper diagnosis before an engine worth thousands of dollars is destroyed.
I hope this is of help. Let us know how you make out. :thumbsup:
Scott,
Thanks for the quick reply. I figured that would be the first step to resolve the issue and topped it off last night. It was indeed pretty low and I maybe put 2 quarts of 50/50 mix into it. I'm about to layer up and see if anything is different this morning. Current temp is 4 degrees. Wish me luck!
Thanks for the quick reply. I figured that would be the first step to resolve the issue and topped it off last night. It was indeed pretty low and I maybe put 2 quarts of 50/50 mix into it. I'm about to layer up and see if anything is different this morning. Current temp is 4 degrees. Wish me luck!
All seems normal again. After topping off the coolant and giving it a test drive this morning we're back in the normal temp range and heat is coming out of the vents. I was really worried that the sound of rushing water was going to lead to something much worse. Thankfully I seem to be in the clear for now.
Hi filmering.
No, the problem is not solved. It just has a band aid on it. The anti-freeze/coolant level should never drop. If it does that means there is a cooling system leak and it will get worse, possibly catastrophic, blowing a radiator hose, radiator, etc., and potentially causing serious and expensive engine damage with the aluminum cylinder head warping from the high heat it will be exposed to from overheating.
Your Corolla needs to be diagnosed by a professional automotive technician. A cooling system pressure test can normally achieve this. A pressure test runs about $30 - $40. The technician should get the car on a lift and look at it from underneath to be able to better see where the leak is. I strongly encourage you to get this done before this problem becomes catastrophic and leaves you or your wife stranded somewhere alongside the road, facing an expensive tow and repair bill. If the leak is not repaired, sooner or later the car will break down.
No, the problem is not solved. It just has a band aid on it. The anti-freeze/coolant level should never drop. If it does that means there is a cooling system leak and it will get worse, possibly catastrophic, blowing a radiator hose, radiator, etc., and potentially causing serious and expensive engine damage with the aluminum cylinder head warping from the high heat it will be exposed to from overheating.
Your Corolla needs to be diagnosed by a professional automotive technician. A cooling system pressure test can normally achieve this. A pressure test runs about $30 - $40. The technician should get the car on a lift and look at it from underneath to be able to better see where the leak is. I strongly encourage you to get this done before this problem becomes catastrophic and leaves you or your wife stranded somewhere alongside the road, facing an expensive tow and repair bill. If the leak is not repaired, sooner or later the car will break down.
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Coolant thermostat sensor? You mean the thermostat right? Or do you mean the coolant temperature sensor?
Assuming you meant thermostat:
On my '96 Mustang GT, anytime I replaced the thermostat, the engine would show it getting to the hot range before the thermostat would finally open. This is because the air pocket doesn't fully get pushed out until the thermostat opens all of the way (thermostats have a small by-pass hole where a little coolant will escape but the air stays above this by-pass hole), and because so little coolant is on the thermostat, it takes a little while longer than normal to open for the first time. Turn on the engine and let it idle, and keep an eye on the temperature. If it gets to the red zone, kill the engine for 10 minutes, then re-start it. Letting the engine get to the red zone and then shutting it off will start to heat soak the thermostat and give it time to open without overheating the engine, then when you restart it, the air bubble should come out as the thermostat will be open, and you should see the temperature drop. You might have to let it hit the red zone twice before it finally opens.
Don't rev the engine at all during this process, you want the engine to warm up as slowly as possible to let the thermostat have time to do its thing.
Assuming you meant thermostat:
On my '96 Mustang GT, anytime I replaced the thermostat, the engine would show it getting to the hot range before the thermostat would finally open. This is because the air pocket doesn't fully get pushed out until the thermostat opens all of the way (thermostats have a small by-pass hole where a little coolant will escape but the air stays above this by-pass hole), and because so little coolant is on the thermostat, it takes a little while longer than normal to open for the first time. Turn on the engine and let it idle, and keep an eye on the temperature. If it gets to the red zone, kill the engine for 10 minutes, then re-start it. Letting the engine get to the red zone and then shutting it off will start to heat soak the thermostat and give it time to open without overheating the engine, then when you restart it, the air bubble should come out as the thermostat will be open, and you should see the temperature drop. You might have to let it hit the red zone twice before it finally opens.
Don't rev the engine at all during this process, you want the engine to warm up as slowly as possible to let the thermostat have time to do its thing.