Apr 11, 2015
RAY: I'm driving down the highway and I see way up ahead one of those diesel tractor trailers spewing from its smoke stacks the vilest, blackest, thickest, most acrid smoke imaginable. And as luck would have it, I'm closing in on the guy and I realize that after a minute or so that he's pulled over to the side of the road, and the thing is running and the smoke is just pouring out.
So I pull up next to him and I put down my passenger side window and I say, "Hey, knucklehead. You're killing everyone behind you. Why don't you shut this thing off?" And he says, "I did. I turned it off, but it won't shut off.”
RAY: And I say to him, "Well, obviously something's wrong. Why don't you stall it out?" He says, "I can't. It has an automatic transmission. But don't worry. In a couple of minutes, the engine will be seized."
I say, "Really?" And I look at an emblem affixed to the side of his truck and in an instant, I know why.
So the question has two parts: Part One is, What did that emblem say? And Part B is, What was going on?
RAY: What did that emblem say?
TOM: Fiat. No? No.
RAY: No. It says, "Turbocharged." And the reason he can't shut the thing off is that the turbocharger has failed and it is sucking the crankcase oil out of the engine.
TOM: We should mention that the way that you shut off a regular car is when you turn the key to the off position, you're stopping the spark from occurring.
RAY: Right. And the way you turn off a diesel is you shut off the fuel. So, you close a valve which prevents fuel from getting from the tank to the injectors, and the engine obviously shuts down, but now with the turbo failed, it doesn't need the fuel in the tank anymore, it's using the motor oil as a fuel. And that's why the smoke is thick and black and ugly and vile and nasty.
TOM: And when the oil is gone, then it's --
RAY: Boom! Who's our winner this week?
TOM: Ah. We have a winner. Congratulations to Melissa Armstrong from Fleetwood, Pennsylvania!