This is not an engine problem and the mechanic who recommended opening up the engine to figure out what is wrong is not a mechanic. You should be getting a new mechanic.
Check the cooling fans. If vehicle is equipped with clutch fan, the clutch could be lacking fluid and loosing speed and air pulling power while operating.
Ensure the fan shroud is intact and in good condition.
Ensure coolant level is correct.
Monday, August 12th, 2013 AT 3:58 AM