A heater control valve is simply a water valve which allows more or less water to circulate through the heater core, depending on how much the valve is opened.he coolant flows  through the heater core all the time.    Temperature is controlled by:    Temperature blend door-control how much air travels through  the heater core -   A small motor that controls the blend door-a rather common  failure point.
In 2002, Tyson fought for the world heavyweight title at the age of 35, losing by knockout to Lennox Lewis. Tyson retired from professional boxing in 2006, after being knocked out in consecutive matches against Danny Williams and Kevin McBride.
James âBusterâ Douglas KO10 Mike Tyson (February 10, 1990) / Fight Purse Disparity: $8.38 Million. James âBusterâ Douglasâs knockout win over âIron Mikeâ Tyson is considered by many boxing pundits to be the biggest upset in heavyweight history and by some sports analysts to be the greatest sporting upset of all time.