why does temperature keep going up on Kia Sedona and engine loses power
You are overheating. Please don't continue to drive it as you risk damaging the engine and being stranded. You will have to diagnose what the issue is, low coolant due to a leak, stuck thermostat, etc.
where is thermostat coolant is ok
and is it easy to change
This link will describe on how to replace. Is it your issue? I don't know. That's why I'm suggesting having it diagnosed before swapping it out......http://www.ehow.com/how_5709168_change-thermostat-kia- sedona.html
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