Kevin said after trying all the hi-tech methods, he went back to the basics.
An engine is just an air pump, it sucks air in, and blows it out.
Plug up either end, the motor woun't run.
That's when he decided to "smell" the exhaust. Either that, or he got so frustrated with the whole mess he decided to commit suicide, and while breathing the exhaust fumes, it came to him.