Honda civic over heating

I have a manual 2000 Honda civic that is acting up. When I drive it after about 15mins it gets really hot. Then right before I pull over it starts to cool off if I have the heat pumping . It also seem to over heat when ever I am sitting idle .

I replaced the radiator and thermostat but I’m still having the problem. Looking for help since I honestly don’t know but my father always told me it was better try and fix something yourself but don’t be afraid to ask for help.

Have you verified that the radiator’s cooling fan(s) is/are operating properly?

You need to see if your fans are working. Open the hood and turn on your air conditioning (engine running). Both fans should be running even if the engine is cold.

If they are running, then the fans are good. Next turn off the AC and let the engine get hot (not into the red zone though) and see if one of the fans comes on. If it doesn’t, you could have a bad relay or temp sensor.

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This vintage Honda is prone to head gasket problems, one of the symptoms is overheating. After you check the fans like VDC and Keith say, check for the head gasket. When you do end up replacing it also replace the timing belt. Very typical repairs for this age Civic.

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Thx guys I’ll check.

When I did the test with AC on with a cold engine only one fan was running. When I turned off the AC both fans were stopped . When the temp gauge got about 3/4 of the way to red the other fan finally kicked on.

To check for a possible head gasket failure, with the engine cold remove the radiator cap.

Start the engine, and while the engine idles watch the coolant in the radiator.

If bubbles begin to appear in the coolant, that’s an indication of a head gasket failure.

Tester

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Looks like you have a bad fan relay. There are three relays for the two fans. The condenser fan which was the one that came on with the AC has one relay. The radiator fan, the other one, has two relays, one to turn it on for the AC and the other for high coolant temp.

There is a fan relay box under the hood that the relays are located in. It should be well labeled. I believe that all three relays are interchangeable so worse case, you buy one relay and you test it in each position until both fans work as they should.

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