•Q. My wife just bought a 2013 Kia Soul, and there is no spare tire. The salesman told us that spare tires are becoming a thing of the past. There is a small unit for putting air in the tire in case of a flat. I was just wondering, why no spare tire? What would you suggest?•
RAY: I would suggest not driving behind any nail trucks.
TOM: There are a number of reasons we’re seeing more and more carmakers ditch the traditional spare tire.
RAY: The first has to do with fuel economy. A spare tire adds weight. A tire-and-wheel combination easily can add 50 pounds to the weight of a car. And since every pound you carry decreases your mileage, getting rid of that spare is an easy way to get more miles per gallon.
TOM: A second reason is space. With fuel-economy concerns leading to smaller cars, making room for an extra wheel and tire is increasingly inconvenient. Most people would rather have that room for groceries, dogs or that giant heirloom Henry XVI Nose Hair Tweezer they find at a garage sale.
RAY: And then on the other side of the equation is the decreasing need for a spare tire. Flat tires are a lot less common than they used to be. Oh, they still happen. But they used to be very common. With modern tires, it’s a very infrequent event for most people.
TOM: There also are other options now. There’s the mini-spare (which will let you travel up to 50 miles or so), the auxiliary pump and can of Fix-A-Flat (which will work for things like nails and small punctures) and, if all else fails, there’s the cell phone and credit card (which works for pretty much everything).
RAY: Those alternatives are not as failsafe as a real, full-size spare that’s checked regularly and kept fully inflated. But carmakers believe that many people would rather have the space and the additional fuel economy these days and just use a temporary spare or call for help if and when they ever need it.
TOM: Of course, if you’re someone who drives in remote areas, on unimproved roads or in places that are out of cell phone reach, you may very well want to consider that when buying a car and make sure there is a real spare tire you can opt for. Or you may just decide to buy an extra wheel and tire and carry it in your trunk.
RAY: But for most people, especially those in populated areas, the cost-benefit equation has been pushing the full-size spare tire out of the car for years. And now, at least a couple of manufacturers have decided that even a mini-spare is not worth making room for. Maybe those cars should come with a factory-installed cell phone in the old spare-tire well?
•Q. I finally figured out what the sound is in my garage. Something on my 2009 Toyota Corolla is running when the car is turned off! I have heard it at various times of the day and night, and also when the car has been parked for hours. There is a noise coming from the driver’s-side rear — behind the tire. It sounds like a fan. It runs for four to five minutes at a time, then shuts off. I called Toyota; they have no idea what it is and want me to bring it in. After taking it several times, I really don’t want to give up the use of my car AGAIN. And it might not turn on until everyone has gone home for the night. Have any ideas? P.S. The car runs fine.•
TOM: Well, first we have to chide you for hanging around your car hours after you’ve shut it off. What are you, some kind of Corolla stalker?
RAY: It’s probably the evaporative emissions system pump.
TOM: Before we were concerned about pollution and smog and asthma and not being able to breathe and all that, all gas caps had pinholes in them.
RAY: That allowed air to enter the tank as the gasoline was drawn out. Otherwise, the gas tank would crumple in on itself, like a baggie that you sucked the air out of. But, of course, the hole in the gas cap not only let air in, it also let gasoline vapors out, and that created ... well, Los Angeles.
TOM: So, an evaporative emissions recycling system is now used on every car. It allows air to get into the tank but stops gasoline vapors from escaping. Instead it stores the vapors in a charcoal canister, and then purges them and sends them to the engine to be combusted when the car is started again.
RAY: What you’re hearing is the evaporative emissions pump pressurizing the system. It does that automatically to check the system for leaks. If it discovers a leak, it’ll eventually turn on your Check Engine light.
TOM: I’m guessing you have a sticky valve or some sort of small leak in the system. It should be covered under your emissions warranty.
RAY: So you can go back to your dealership and point them in the direction of the evaporative emissions pump, and ask them to check it out.
TOM: Or, alternatively, stop loitering in your garage, leave the car alone and don’t worry about it until the Check Engine light comes on. Good luck.
Got a question about cars? Write to Click and Clack in care of this newspaper, or email them by visiting the Car Talk website at www.cartalk.com.