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04 honda civic hybrid overheating

Hi all! (Be forewarned, I’m a girl and need help lol)

I could us some advice. I recently bought an 04 honda civic hybrid and within 20 min of purchase the check engine light came on so I stopped at auto zone to have them pull the codes, then the car wouldn’t start. Long story short it ended up being a busted radiator and the fans weren’t turning on so the car kept overheating and wouldn’t start when it was too hot. We also changed the thermostat.

Fast forward to now, the car was running very sluggish so we changed the spark plugs and it made a HUGE difference. Nowww I have to fill her with water every time I drive her and she runs hot/overheats after about 20 minutes of driving.

I’ve been told it’s a bad engine, but don’t understand how the car can run well until she overheats if that’s the actual problem.

Are there any tests that I can do or short term fixes and can try? I just started a new job today and won’t get paid for at least a week or two. Any suggestions help greatly.

When the engine is cold, remove the radiator cap.

Start the engine, and while the engine is idling watch the coolant in the radiator.

If bubbles start to appear in the coolant while the engine is idling, that’s an indication of a blown head gasket.



One possible explanation, metal’s expand with temperature, so if the engine insides gets too hot, the moving parts no longer fit together properly, causing increased friction & poor engine performance. . Electronic engine sensors can also be adversely affected by high temperatures.

One simple thing you could try is to replace the radiator cap. I must say I don’t think that will work in your case, but it is something to try that doesn’t cost much and could possibly work. It’s critical that the radiator fans are turning on and off at the correct temperature too. You might could ask a shop to just test that, shouldn’t cost too much. And if you are able to see where the coolant is going, leaking, or white smoke out the tailpipe, that’ll get you to a diagnosis quicker.

Water shouldn’t be used in the cooling system btw. Water offers no freeze protection or rust & corrosion protection, and doesn’t properly lube the water pump. When you say you need to fill her with water, I presume you mean a 50/50 mix of anti-freeze coolant.

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You probably weren’t the first person to over heat the engine, I suspect the engine was already damaged when you bought the car.

The engine can still run and need to be replaced if the head and block are warped and it won’t hold coolant.

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Did you get the non running cooling fans fixed?

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I didn’t know that, I always thought you could use just water…

With that being said is it too late for me to do the 50/50?

Yea I bought her from a guy that got in at an auction and he knew damn well there was issues with it when he sold it to me. (Wouldn’t return any of my phone calls after the purchase. :pensive:)

Yes, they work now but I’m not 100% sure if it’s at the right times.

When I stop the car after driving for about 20 minutes I can hear it either hissing or bubbling. Which I’m assuming is the water from overheating.

Also I looked at the exhaust today and it’s just a thick black substance. Nothing white.

The less time the engine internals are exposed to plain water the better, so replacing the plain water with 50/50 now is still a good idea.