Overheating

BENNYB43

MEMBER
2003 HONDA CIVIC
1.7L
4 CYL
2WD
AUTOMATIC
175,000 MILES

My car listed above (LX) was overheating periodically. It wouldn't overheat right away. I keep adding water about once a week and that seems to prevent overheating. I changed the thermostat to see if that would fix the issue, but still overheats. Next, I added "stop leak", this stopped the water leak, but now it overheats faster after driving about 2-3 miles. With the stop leak it appears no water is leaking from anywhere. I can also confirm the radiator fans are working and that is not the issue. I also replaced the water pump about 2 years ago and don't think that is the issue either.

I think using the "stop leak" was the wrong move as the overheating seems worse now.

Any idea what I should do next to stop the overheating?

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,747 POSTS

Hi,

If the thermostat is new, the stop leak may have caused an issue, but there could be a different issue.

The first thing I would try is to drain and flush the cooling system to make sure there isn't a partial blockage in the radiator or engine block. Here is a link that shows how that is done:

https://www.2carpros.com/articles/coolant-flush-and-refill-all-cars

Also, prior to the stop leak, could you tell where the leak was coming from?

Next, if the flush doesn't help, you bled the cooling system of air, and the system is full with no leaks, we need to check for a possible head gasket issue. Take a look through this link. It explains what to look for.

https://www.2carpros.com/articles/head-gasket-blown-test

If nothing is found there, I need more information. For example, are there any diagnostic trouble codes stored in the computer? Does the vehicle run normally prior to overheating? Is the radiator (front) restricted in any way? Are there any odd smells, sounds, characteristics of the vehicle you notice?

Let me know.

Joe