Q: I have a 2014 nissan maxima. It smoking from the exhaust with a blueish gray look. There's no oil leaks on the ground.

Hi there. Check the engine oil level and see how low it is. If the oil is a little low, then the oil is burning in the exhaust system. This is caused by the valve guide seals leaking, the rings not seating, or the PCV (positive crankcase valve) not releasing properly causing too much pressure in the crankcase. Check the intake and air filter for any signs of oil. If oil is present in the intake or air filter, the change the PCV. If the air intake is clean, then check the compression on the engine. The first puff of the compression should be half of the max puff. This will tell you that the rings are sealing. If the first puff is very low, then the rings are not sealing properly. You can put in sea foam in the fuel tank and in the engine oil to clean up the rings to seat them. If the puff is half or higher, then the valve guide seals need replaced. If you need further assistance with your engine burning oil, then seek out a professional, such as one from Your Mechanic, to help you.