White smoke from the tail pipe. Problem?

Dear Car Talk

Dear Car Talk | Oct 01, 2000

Dear Tom and Ray:

I have a brand spankin' new Nissan Maxima. About three days ago, it did the weirdest thing. It started right up, but immediately started making a weird noise. And at the same time, it blew thick plumes of white smoke from the exhaust. The smell of the exhaust was heavy with gas. It lasted for about a minute, then the sound went away, but the smoke continued for another few minutes. It has not happened since. I'm not sure whether to take the car to the dealership, since it hasn't recurred. What happened? Did I buy a lemon? Is it a serious concern? -- Cindy

RAY: I think the nozzle on one of your fuel injectors got stuck, Cindy.

TOM: The way the injectors work is that they're ordinarily closed. And when they get a "pulse" from the car's computer, they squirt gasoline under pressure into the cylinder.

RAY: But if something goes wrong, or if something gets stuck in the injector -- like a piece of dirt or some guy's wristwatch from the factory -- the injector can get stuck in the open position and flood the cylinder with gasoline.

TOM: While the cylinder is flooded, the car would be running on only five cylinders. That's why it made a "weird" engine noise. Then, once the injector unclogged itself, it would still take the engine a few minutes to burn through all of that excess gasoline. And that's why the smoke continued even after the noise stopped.

RAY: It's possible that the clog was just caused by some small piece of dirt that was accidentally left in the fuel system or gas tank at the factory. That shouldn't have happened, but it might have. And if that's the case, it might never happen again.

TOM: But if it does happen again, then one of the injectors is probably faulty. In that case, I wouldn't hesitate to ask your dealer to replace the injectors. After all, this car is brand spankin' new. And shouldn't it run like it?

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