Q: Dear Tom and Ray:

I have a 1988 Chevy Nova with 115,000 miles on it. It is well-maintained. During the summer, it gets a decent 34 miles per gallon, but in the winter, it gets only about 29 mpg on the same highway with the same driver. Why?

--Brian

A: TOM: 'Cause it's cold out, Brian baby! Look at my brother. He eats 11 pink-frosted doughnuts on the average winter morning instead of his usual eight during July and August.

RAY: The reason cars run less efficiently in cold weather is because gasoline doesn't vaporize as well. The carburetor sends vaporized fuel into the cylinders, and in cold weather, some of it condenses and turns back into liquid gasoline. That portion doesn't burn and is essentially wasted. And that accounts for most of your 15 percent reduction in mileage.

TOM: Most cars spend more time warming up and idling in the winter, and in some areas there's more wind resistance as well. But the loss of efficiency in gasoline combustion due to cold weather accounts for the vast majority of the lost mileage.

Q: Dear Tom and Ray:

I have a '95 Kia Sportage, which, on the whole, I have liked very much. About a year ago, though, one of my power windows broke, causing the glass to slide down into my door. The window wouldn't go up anymore. The dealership said it would cost about $350 to fix, so I had them put a block under the window instead to keep it closed. A few weeks ago, it fell into the door again, and I had to have it re-blocked. In the past month, two more windows have taken a dive, so to speak. Is this something with Kias, and is there some recourse? Can I get a kit to convert the car from power windows to manual windows? Thanks.

--Dina

A: RAY: I don't know of any kit that turns power windows into roll-up windows, Dina. I've seen electric sunroofs with "emergency cranks" (because if that motor fails in the rain, you're in real trouble), but there's no such kit for windows as far as I know.

TOM: And in general, I'm afraid you're out of luck. You bought a cheap car. You got a great price, right? You even say that, on the whole, you like it very much. But most cheap cars are cheap because their components are, what? Cheap! And although there's no technical service bulletin on the window regulators, my guess is that they were underdesigned and probably are failing for other Kia owners as well.

RAY: My advice would be to look for a special on "blocks." If money is an issue and you're not planning to keep this car forever, I'd use blocks for all but the driver's window. That one you're really going to have to fix. You'll realize that after you miss a few "exact change" toll buckets while leaning out the door and have 80 gazillion cars honking at you and using unfriendly hand gestures.

TOM: Or when you ride with my brother the morning after he's eaten a meatball sub.

RAY: But that's the chance you take when you buy a bargain-price car, Dina. Overall, you may have done well--even after you pay for repairs. But annoyances like this one are the risk you take when you buy a Kia instead of a more expensive Honda or Toyota.

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(C) 1999 by Tom and Ray Magliozzi and Doug Berman