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Car: 2001 Honda Civic - D17a

Problem: over heating at speeds over 120/130 Km/h

What happened:
I drove pass my friend (who love to race), driving in 5 gear at about 130/140 km/h, after I reach a distance, I saw him speeding to catch me, suddenly he was at my bumper.

I then changed the gear from 5th to 3rd, I heard the compression come in, then I immediately go to 4th then 5th.

After, about 500 meters, I saw the temperature guage in the hot zone.

What could have gone wrong?

 
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Today, I observed then the over heating problems still remains, anytime I drive over 120 km/h.

 
Rep Power: 812

hmm weird, ive never seen overheating happen from doing that. its possible its just a coincidence. after driving your car, check how hot the two radiator hoses are and that should at least tell you if thermostat just went bad.

 
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The same time it happened, when I reach my destination, I felt the top radiator hose and it was extremely hot.

 
Rep Power: 812

okay what about the bottom hose, was it as hot or just warm?

 
Rep Power: 388

The top hose should be hot, the bottom hose should be cooler.

Do your fans come on... if they dont, its your fan switch
If your rad is in good shape and you have coolant, and your fan switch is good, its most likely your thermostat that needs to be replaced. Also make sure you haven't messed with your gauge cluster lately, because it could simply be a fact that the needle was taken off and put back on incorrectly- displaying the wrong temp.

 
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Fans are working ok, radiator is full with oil based coolant.

This over heating all started after the high compression from 5th gear to 3rd gear.

 
Rep Power: 812

did you go above redline when downshifting?

 
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So what would go wrong it this happens?
and how to fix it?

 
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The thermostat was removed by previous owner when I checked.

 
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I rod out the radiator and change the hose.
The radiator was clogged.

Now the car is running fine.