Q. Recently I took my 2003 Toyota Camry to the local dealer because the “check engine” light was on for a couple of days. They replaced a sensor at a whopping cost of $550. I was told that if I did not replace this sensor ASAP that my catalytic converter could be damaged. During that visit the service advisor informed me that I also needed to replace the “intermediate steering shaft” at a cost of over $500. My question to you is, how will I know when this part wears out? Will I be able to steer the car? How important is it that I change this part? Currently I do hear a slight noise when making turns. My car has 45,000 miles on it.

— Donna, Cumberland

A. Toyota has issued a technical service bulletin that describes a noisy steering shaft. The repair lists only lubricating the part— not replacing it. Have the dealer or an independent repair shop reference TSB number ST002-03. Lubricating the noisy part should only take 15 minutes.

Magnets on the fuel line?

Q. I see on the Internet that you can allegedly gain an increase in gas mileage by using magnets that oppose each other on a rubber fuel line. They say it break downs hydrocarbons in gasoline. Does this work, or is it just another way to make a quick buck and take advantage of the public?

A. I have seen these magnets—and even tried them—and found no benefit at all. The EPA has tested many other products, and found little or no benefit. If a suggestion seems too good to be true, it usually is.

Getting rid of glare

Q. I have a friend who owns a 2008 Saturn Astra XE 5-door sedan. She complains of defroster vent images appearing as a glare in the center of her windshield as she drives. We have no solution to offer. Do you know of any similar complaints, and can you offer a solution? Depending on the angle of the sun and the slope of the windshield, you can see the glare. She is an elderly driver and she feels it is a hazard to her driving.

— Richard

A. Car manufacturers are usually pretty good about trying to limit glare. The problem is that drivers come in all different shapes and sizes. I recently road-tested an Astra, and didn’t find any problems with glare. You could try raising the seat up a bit, and sitting at a slightly different height may help. In addition to changing your driving position, try putting a dark cloth across the dash. This may limit some of the reflective glare.

Possible computer glitch

Q. We have a 2008 Jeep Patriot and the problem is that at times, the transmission won’t shift from low to high without stopping and shifting to neutral, then back to drive. Once we do this the Jeep is fine. The dealer has looked at it and found nothing to indicate a problem. Do you have any suggestions?

— Richard, Glocester

A. The symptom sounds like a computer issue. By stopping and shifting into neutral, you are in essence resetting the computer. At this point, I would have the dealer document your experiences and contact Chrysler for technical assistance.

Air suspension sagging

Q. I have a 1992 Lincoln with air suspension. Recently, the air suspension light came on, but the car seemed fine. I checked, and the fuse was bad. I replaced the fuse and then several days later the rear of the car sagged and felt as if there were no shocks or springs. When this happened the warning light never came on. I went home and replaced the fuse, which looked okay, and the car leveled out. What should I do?

—Robert, Warwick

A. It is possible that the fuse connector is damaged, and that the replacement fuse didn’t make a good connection. I would recheck the fuse holder, as well as any connections to the pump and switches. Once these air suspension systems fail, they can get very expensive to repair. In the last few years, kits have come out that replace the air suspension with conventional springs and shocks. If you are not extremely fussy, this is a more economical alternative to the factory system.