Q-What is your take on water/vinegar fuel cell add-ons for cars? Some are do-it-yourself kits. Some, like the Mag Drive, are professionally installed. Not that I’m interested in installing them in my vehicles, but allegedly gas mileage is greatly increased and emissions are 70 percent lower.
—J.M., Tolland, Conn.
A-If it sounds too good to be true, it usually is. The Federal Trade Commission even has a Web page titled ‘Gas-Saving Products: Fact or Fuelishness?’ http://bit.ly/ev1l4Y that discusses all the gadgets and gee haws that just plain don’t work. The Environmental Protection Agency periodically tests alleged fuel- and emissions-improvement devices. If you would like to see what devices EPA has evaluated and their results go to epa.gov/otaq/consumer/reports.htm.
Q-I went to buy new tires for my ’09 Camry, and was told that the tires must be V-rated. As I recall, V-rated tires have a speed rating of 150 mph, are considerably costlier than S- and T-rated (110 mph and 120 mph, respectively) and only have about half the life (40,000 vs. 80,000 miles). My question is why would a 4-cylinder Toyota Camry require such an expensive tire? What happens to performance if I buy T tires, for about a third the cost?
A-Our knee-jerk answer is that S- or T-rated tires would be OK, but we don’t want to look like a jerk (knee or otherwise), so we posed your question to an expert at Goodyear, who stated: “Generally, it is recommended that a speed-rated tire be replaced with a tire having an equivalent or greater speed rating. However, if you never drive at speeds near the limits of your speed-rated tires, you may choose to replace them with tires having a lesser top-speed rating. In situations where tires having different top-speed ratings are mixed on a vehicle, the maximum speed certification is limited to the top-speed certification of the tire with the lowest speed rating. Speed ratings do not indicate how well a tire handles or corners. They certify the tire’s ability to withstand high speed, although it is true that a V- or Z-rated tire is often also designed to provide enhanced responsive handling.”
Q-Is there any such thing as a self-charging battery? I was told this by my dealership when I took my 2007 Chevrolet Aveo in to see what the starting problem was. I would drive for awhile, stop to shop, and when I went back it wouldn’t start. If I waited 10 minutes, it would start. I wrote to Chevy in Detroit and the dealer installed a new battery. If there is not such a thing as a self-charging battery I need to find a new dealership.
—J.K., Bethlehem, Pa.
A-No, there is no such thing as a self-charging battery. However it is possible that the battery can recover somewhat after being run down trying to start the car. We won’t go into the chemistry, but resting for awhile can allow ions to exchange. Your problem may stem from too many short trips, especially in the winter when you use many electrical accessories. If you don’t do some extended driving, the battery may not get fully recharged between trips.
Q-I have a 2002 Dodge Grand Caravan with 108K miles on it. I have a thumping noise coming from the front. It sounds as if there is a flat spot on one of the front tires, however there is no flat spot. I have had the shocks replaced, new bushings on the sway bar, front end alignment, new struts and a brake job and they tell me that the front end of the car has no problems. The noise is there and no one can pinpoint the cause of it. What do you think it could be?
—B.B., Ellington, Conn.
A-We think you are on the right track. There were problems with the sway bar bushings on that vintage of minivans. Did you replace the sway bar links when you replaced the bar and bushings? Another common problem is the upper strut mount and bearing assembly.
Q-Regarding timing belts, why do all of the automotive manufacturers utilize a rubber belt instead of a steel timing chain? It would seem that a chain instead of a belt would last indefinitely. Or is this just a stupid question?
—D.K., Chicago
A-Actually, we are seeing a return to timing chains on many engines. Belts have been used because they are quite quiet and can make tight turns around pulleys, but chains have come a long way. You’re right, chains last almost indefinitely.
Q-I have a 2004 Toyota Camry that has 86,000 miles, and is due to get the timing belt replaced. This is a very expensive maintenance item. We will be getting a new car around March 2011, and I would like to know if we buy a car with a timing chain instead of a timing belt, would that be a good move to save on the maintenance?
—S.H., Chicago
A-Yep. See the answer above.
Bob Weber is an ASE-certified master auto technician. Send questions to Motormouth, at motormouth.trib@verizon.net.
