Car keeps overheating
I have a 2001 ford focus it started running
hot after my battery went bad i changed
thermostat and thermostat housing plus
resvior i dont know what else it could be
(1) check operation of cooling fans, they should come on with AC on. Check they are coming on when engine gets hot. (2) Flush out and check the flow in your radiator (http://www.howacarworks.com/cooling-systems/how-to-flush-an-engine-radiator), (3) check water pump for flow, squeeze upper rad hose when engine is hot (and thermostat is open), it should have coolant flowing under pressure to radiator. If not water pump may be worn, even if it isn't leaking.
Check your cooling fans
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