Changed thermostat andcleaned the radiator, engineoverheatwhen going uphill or in heavy load only. Looks like I have a air pocket in the cooling system ?or maybe something else? I can't the find airbleeder on this car (2005 civic). Pls Help! Thanks.

 

When engine is cool, fill reservoir and radiator to max levels.

Install radiator cap loosely, set heater level to max heat, and run engine until radiator fan comes on twice.

Turn engine OFF, and top off the reservoir and radiator.

Tighten radiator cap, and the bleeding process is done.
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If this bleeding doesn't help, check whether the radiator fan fails to come ON when engine is hot.

Alternatively, you might have a blown head gasket.

 

Also the temp will go all the way to the H, but the upper hose is not really hot, I continue running the car and the temp will go down to normal temp. And no sign of coolant in the dipstick, radiator coolant is also clean(no sign of oil). I'm thinking of changing the ect, what do you guys think?