2012 GMC Acadia 3.6L I replaced all the fuel injectors. Then I cleaned the MAF Sensor with CRC MAF Sensor spray cleaner. Then I Cleaned the throttle body and intake valves with CRC Intake Valve and Turbo Cleaner. After doing that the engine fan continued to run for about 45 seconds after shutting the engine off. I figured it was just a little hot from all the engine revving during the valve cleaning. But after I let it sit for an hour before driving on the highway to clean out the valve's some more, it seems like the fan runs constantly. It only ran after shutting off this time for 10 seconds or so, but turns on immediately upon start up, even when cold, and does not shut off the entire time.