Q. My wife has a 2007 Toyota Solara Convertible with 26,000 miles. I brought it to the dealer because the headlights were not working properly. As part of their check-up they wanted to replace the cabin air filter for $140. I’ve never heard of a cabin air filter. Is this service necessary? Is $140 reasonable?

A. Cabin air filters help filter dust and pollen out of the air before it goes in to the heating and air conditioner system of your car. In many cases this filter is one of the most overlooked in today’s cars. As the filter starts to clog it will limit the air flow from the heater or air conditioner. Although there is a specific period to replace any filter, the common sense approach is to replace it when it is dirty. The price quoted is expensive. Alldata, the technical database I use, lists the factory Toyota filter price at $32.50 and 20 minutes labor time to replace the filter.

Get a booster seat

Q. I have a 1995 Dodge Caravan and none of the backseats have headrests. I have been looking online and can’t find any aftermarket headrests without DVD players. I have toddlers and use booster seats but worry about whiplash. Is there is an attachable headrest that mounts onto the seat without unnecessary electronics?

A. Although there may be a company that sells an add-on head restraint, I wouldn’t use one. There is no way to tell how they would hold up in a crash. Depending on the ages of your children, a high-back booster seat could be the answer. Some high-back booster seats can accommodate children up to 100 pounds.

Rubbing alcohol works

Q. I recently took my car through a full-service car wash and got "the works,” which included a spray-on waxing. I now have an irritating film on the exterior of my windshield that seems impossible to remove. I have tried using my windshield wash solution and household window cleaner and still there is a film. Is there a product that you can recommend that will remove this film? Thanks for your help, and I enjoy and benefit from your column, keep up the good work!

A. I have found the best product to remove this type of wax is rubbing alcohol. Start with a mix of 50/50 water and alcohol. If the film is still there after cleaning try a stronger mix of alcohol. Be cautious using alcohol around delicate plastic, rubber, or painted surfaces.

Delaying the bushings?

Q. I have a 1996 Toyota Camry and a mechanic recently told me that I needed to replace the sway bushings on the wheels. I asked if it could wait awhile to be done, and he told me that it wasn’t dangerous to drive without having them replaced now. Is it dangerous to drive and expensive to repair?

A. The front anti-sway bar is held in place with two bushings and stabilizer bar links. It is usually the actual bushings that mount the stabilizer bar to the body of the car start to creak and groan. Although it is not dangerous, the problem will not improve. The cost of the repair is approximately $75.

Buy the vehicle you like

Q. Considering the weather this past winter, I really want to buy a small SUV. I have two in mind, a 2008 Honda CRV and a 2008 Toyota RAV4. They are both used with similar mileage, four-cylinder engines and options. Which one do you prefer?

A. I prefer the Honda CRV, I think for it offers more practicality and a slightly better ride. I also feel the four-cylinder engine in the CRV performs better than the four-cylinder engine in the RAV4. Finally, I never liked the Toyota design of mounting the spare tire on the rear door. But the real answer is to buy the vehicle you like to drive.

Repairs adding up and up

Q. I have a 2001 Mercedes E 430 with all-wheel-drive with 80,000 miles. I love the car, but I’m very frustrated concerning things that go wrong that just don’t seem like they should. The rear window drops into the door (a $600 repair), a blinker won’t go off (a $350 repair); it seems as if this car requires one expensive repair after another. For a car of this stature, it just does not seem right. Your opinion: put up with it or sell?

A. As any car ages it is likely to have mechanical problems, even a Mercedes Benz. In fact the cost of a car has little to do with the vehicle’s reliability. Luxury cars can be faced with more expensive repairs due to the complexity of the systems in the car. A basic car without stability control, navigation system, and heated and cooled seats may actually have far fewer problems. Concerning your car, it is always cheaper to fix an old car than to buy a new one. As you have pointed out, however, as the car gets older you are faced with dependability issues. And it is these issues that typically have people looking for a new car.

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