What Engine Blow-By Looks Like
When an engine is experiencing blow-by, basically what is happening is a piston ring failure where the ring simply is not making a tight seal with the cylinder wall for whatever reason. As a result, air and fuel mixture will escape into the crankcase where it shouldn’t be.
The result of such a failure will be the phenomenon that is known as blow-by. Essentially, the byproduct will be lots of smoke and a choppy, misfiring sound much like you see in this video.
According to the mechanic behind the camera here, this is one of the worst cases of blow-by that he has ever seen and to make it even worse, this case just so happens to be on a brand-new car with less than 20,000 miles on it. That has to suck big time for the owner.
Check out the video below as he shows us all of the symptoms. When he popped off that oil cap and smoke was chugging its way out, we knew that this thing was a lost cause!