Dear Tom and Ray: Help me out here. I need to know if I have to start wearing my flameproof sweater next time I fill up at the neighborhood gas station. The last two times that I filled up the tank at the local gas station, there were Richard Petty wannabes filling up their cars with the engines still running.
Now, I know illiteracy is bad in this country, but do people really not understand the words "turn off your engine while refueling"? Should we pay attention to these signs, or should we all just ignore them?
Tom: Here's why we should obey the signs. When you're refueling a car, gasoline vapors are generated. And there's always a possibility that gasoline will spill and vaporize.
Ray: And when gas vapors meet a spark, the result is . . . kaboom. So it makes sense to do everything possible to reduce the chances of blowing yourself and other innocent people into the big filling station with clean restrooms in the sky, right?
Tom: And while random sparks are not normally created by most cars, it can happen. If you had a bad spark-plug wire, for instance, and the spark was jumping, under just the right (actually wrong) circumstances, it could ignite the vapors and take you and all those S&H green stamps with it.
Ray: On the other hand, when the engine is off, there's almost no chance that a spark will ignite the gasoline fumes. So why not cut the risk to zero? Are we that lazy that we can't shut off the engine for five minutes while we refill the gas tank?
The color of oil
Dear Tom and Ray: I'm an old Yale Divinity School graduate with a question for you. Why don't any auto makers make an oil dipstick of any color except steel? That's the exact color of clean motor oil! A different-colored dipstick would make it a lot easier to read the oil level, wouldn't it?
Ray: I'm not so sure, Garrett. While a white dipstick might make it a little easier to read, I think the bigger problem is that the oil has no color when it's new. Although it looks amber in the can, when you have only three molecules of it on the dipstick, it's practically transparent.
Tom: Right. Once it gets good and black and gooey, you have no problem distinguishing the oil from the dipstick. That's why I haven't changed my oil since 1976.
Ray: My brother has all the solutions, doesn't he? We need to hear from some Divinity/Mechanical Engineering double majors in our audience. Has anybody addressed this problem? Let us know by writing to us care of this paper, or e-mailing us through the Car Talk section of www.cars.com.
A dying fuel pump?
Dear Tom and Ray: I have a 1986 Nissan Pulsar NX with a five-speed transmission. Recently, it has developed an annoying habit of dying a slow (30- to 45-second) death, complete with shivers and shakes. But up to that point it seems to run perfectly. I took it to the nearby Nissan dealer, but it was no help. What would cause the car to run just fine for a few miles, and then start bucking, kicking and die?
Ray: A sudden lack of gasoline would cause just this kind of behavior, Theo. And that could be caused by a bad fuel pump.
Tom: And you don't say how many miles are on this car, but since it's a 1986, I think we can safely assume that you've got at least half-a-bajillion. So, assuming that your dealer already checked the fuel filter, the next thing to do is ask your mechanic to check the fuel-pump pressure. If it's below spec, put a new fuel pump in there.
Ray: If the fuel pump is OK, the next thing to look at would be the secondary gas filter located inside the carburetor. In this car, that filter sometimes gets plugged up and causes fuel interruption, mostly at high speed. You have to take the carburetor apart to change that one. Good luck, Theo.