Q: It seems that you have previously given tips on eliminating the terrible cigarette odor in a used car, but I can't remember. This car has a leather interior, the cabin air filter has been replaced, sprays have been used on carpeting, but to no avail. The car is in great shape except for the nauseating smell! Can you please provide some suggestions?
B.M., Crete, Ill.
A: Most of the products you can find in auto parts stores and variety stores are scented coverups. The most effective and long-lasting way to eliminate odors is with ozone. Ozone is a three-atom variant of oxygen and is not something you will find on any shelf. It can be toxic. Many professional detailing shops have ozone generators that can remove just about any stink. Expect to leave your car for a couple of hours or more. All of your personal belongings must be removed, the floors and seats vacuumed and other surfaces cleaned as necessary. If the car has a cabin air filter, remember to change it often. If activated charcoal filters are available, go for them.
Q: I usually buy gasoline at a station where the pumps have no sign or notice that the gasoline contains ethanol. Can I assume that I'm buying pure gas, or can ethanol be added without notifying the buyer?
J.D., Cassopolis, Mich.
A: Michigan is among several states that do not require labels when ethanol is blended into gasoline. So no, you cannot assume that you are getting pure gasoline. Some retailers do offer pure gasoline, but when they do, the price is significantly higher. Let that be a clue as to what you are pumping into your tank.
Q: In 1967 while in school in San Diego, a local took us up to see the Mount Palomar telescope. On the way down, after the last curve, and while on a long descent along a straightaway leading to a flat stretch, the driver said: "I have no brakes." The old drum brakes had overheated and would not grip. We coasted to a stop and waited for the brakes to cool and regain their function. Scary! Ever since, I have always downshifted to use engine braking, even long after the industry shifted to disc brakes. I think people riding with me may have thought me a little weird. After reading your column, I'm glad I always did it, and not just because of the brake wear you mention.
A: Drum brakes were notorious for overheating during extended application. That is why they are found only on entry-level small cars and only on the rear. The rear brakes generally provide only 20 percent of the braking. Another issue with extended brake application is boiling brake fluid. When any liquid boils, it turns to a gas and gases are compressible so the brakes fail. DOT 4 brake fluid has a higher boiling point than DOT 3. Even more importantly, any water in the hydraulic system will boil long before the brake fluid, so it is a good idea to flush and replace the fluid from time to time. By the way, cars with manual transmissions are perfect candidates for engine braking.
Bob Weber is a writer, mechanic and Master Auto Technician.