Q: Engine oil leak

Hello there, thank you for asking about your 2007 Mercury Mountaineer. This is a fairly common issue on many cars. Your car is equipped with a V-8 motor which has two separate "sides" of the motor where the cylinder heads are located. Oil leaks can be common near or around these as they have a valve cover on top of them where the valve train components are. Valve cover gaskets are a common source of oil leaks which would cause it to leak possibly from only one side. I would recommend having an expert from YourMechanic come to your home to diagnose and修理阀盖垫圈。