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Heater not very hot and small antifreeze leak

I have a 99 Toyota Camry. My heater is not as hot as it normally has been and I have s small antifreeze leak as well.could it be Abad heater core? What are signs of a bad heater core?

Also my temp Gage is not reading normal temp like half way, it’s ready between a quarter and half which is odd to me when running for a while.

It could be the heater core, or it could be leaking somewhere else. If the heater core is leaking, you’ll eventually smell antifreeze inside the car and the floorboard/carpet will eventually get wet with antifreeze. You really need to find and repair the leak, wherever that is, and then worry about the heat later. Since we know the car’s leaking antifreeze somewhere, chances are that you’re a little low on antifreeze and the heater core has a little air in it rather than antifreeze. Filling the system with antifreeze might get your heat back working, but you’ll need to address the leak eventually.

Ok, so the temp gauge reads colder than normal and the heat does not work? If that’s the case, the thermostat is most likely stuck open. The car should still be driveable/not overheat, but the heat will not work as well because the coolant isn’t getting as hot as it’s supposed to.

I check the antifreeze everyday and top it off. I got a new radiator and alternator in the summer.

How do I get the thermostat unstuck? Is there a way for me to check ? I’m a single momma and my ex husband is a mechanic but won’t help me at all! So if I can do it myself I will damn sure try!

The car is driving fine and not overheating.

You have to buy a new thermostat. They’re pretty cheap, though. There’s probably a YouTube video on replacing the thermostat on a car like yours. You might look at a video and see if it’s something you want to tackle. If you did the radiator yourself, I’m sure you could do the thermostat.

The car will drive fine and not overheat with an open thermostat. It’ll run at a colder temperature than it’s supposed to…and your heat will be kinda not so hot.

I wish I could say I did the radiator but I hat it and alternator replaced at local garage. Actually where my ex-husband used to work for 10 years so I know the owner very well. I will probably have him look at it on Monday. Can I still drive it like this until I can get it looked at? Is there anyway I can look and see if it’s stuck?

I really appreciate all your help!!! Very much!!

You should be fine driving it. The only way to look at it would be to take it out, and since they’re cheap (probably less than $20), if you were going to the trouble of removing it, might as well replace it. On most cars, the thermostat is underneath a housing where the top radiator hose connects to the engine. You’ll lose coolant removing it, so I’d just replace it. There’s a chance that the thermostat isn’t the issue and your gauge is wrong, but if you drive a while, heat doesn’t get hot, and the temp gauge reads colder than normal, chances are the thermostat has failed open. At least it failed in the open position. If it had failed in the closed position, the car would overheat.

I believe my gauge is working cause it was overheating in August when I replaced the radiator. Thanks for all your help. I will gave my guy check it out on Monday. Thanks again and have a great night!

One more question could my thermostat be leaking antifreeze?

No, the thermostat itself couldn’t be leaking, it’s sealed in the engine under a housing. Good luck. Should be an easy repair for your mechanic. Ask him to see if he can spot the leak while he’s in there.

My wife had a 99 Camry when we got married. It was a good car, but developed engine problems at around 208k miles and we traded it off before it finished dying lol.

I’ve had to replace the thermostat on my Corolla a couple of time over the years for the same reason, engine running cooler than normal. The thermostat deforms over time and doesn’t close completely like new one will.

Re the cooling system leak. Do you know where it is leaking? Anything dripping on the ground under the car so that you see a puddle in the morning? Or is it leaking inside the car and you see coolant puddling on the floor of the passenger side? =The most common places for cooling system leaks are the radiator and the water pump and the hoses connecting to those parts. A thermostat housing can leak, which will create a visible leak that drips to the ground, but that’s not a common thing.

If you’re not a diyer at this point, suggest to let the shop change the thermostat. If you asked they might let you watch how they do it. It’s not that difficult of a job but if done incorrectly, that mistake could wipe out the engine is the problem. Cooling system leaks should be corrected with due speed, b/c even a small leak prevents the system for properly pressurizing, which can lead to overheating and engine damage. In the meantime be double sure that the radiator is topped off as needed. When you have a leak it’s not sufficient to top off just the plastic bottle, you need to check the radiator’s fill level too.

If you have a significant amount of coolant disappearing (say, a cup every few days) with no visible leak, you might have a blown head gasket.

A coolant leak lets air into the system, the heater core is one of the higher points of the cooling system and air in that would explain the lower temp. If there is air where the coolant temp sensor is the gauge will read lower because it isn’t in the hot antifreeze.

Get the leak fixed, the antifreeze topped off and the air bled out of the system.

1 Like

had to change my thermostat on my nissan real bear had to remove power steering pump off bracket bring back 1960 technology.

Good advice. :+1: