Hey guys my brother has a 02 Chevy Blazer I work on and it's over heating so I replaced the thermostat and it didn't fix the problem and to make it more interesting when the temp hits 210 the rpms increase when you hit the gas pedal tho know of the power goes to the wheels I thought the tranny might be going bad but when it's cools down it's fine no problem with the tranny so I am thinking about changing the water temp sensor tho I never had a vehicle act like that any suggestions would be greatly appreciated and thanks in advance

 

What condition is the coolant in? Is it Dexcool or regular "green" coolant?