Dayton Daily News

Wheels: Roy writes, “I read your column in the Dayton Daily News weekly and thought that you might be able to offer a suggestion to help me resolve a brake light problem on my wife’s 1999 Oldsmobile Silhouette.

About every 30 to 60 days for the past six months, I have had to replace the left brake light bulb (the top bulb in the four-lamp taillight assembly). Each time, I find that the plastic base of the bulb (#3057) is melted around one of the four contact pins. The bulb itself is not burned out, but the melted base prevents contact between the pin and the contacts in the socket. Do you have any thoughts on what might be causing this? Your advice would be greatly appreciated.”

Halderman: The melted plastic indicates heat (obviously), and this is usually due to high resistance at the connection with the bulb.

The best way to repair this is to replace the bulb socket. This part may not be available as a separate part so be prepared to replace the entire tail lamp assembly. You may be able to get a small pick into the socket and pry the contacts toward the center where they can make a better connection.

Wheels: An e-mail from Joe says, “I am told it is wise to run a tank of premium gas through the engine once a month. I am also told the computer in the car adjusts for the type of gas. Are these in conflict?

Halderman: The use of premium fuel in a vehicle designed to use regular-grade gasoline will not help anything. I think this idea came from about 20 years ago when premium had more injector cleaner than regular. Now all grades have about the same amount, so using premium gasoline will not be a benefit. However, I do add one bottle of Techron to the gas tank of my vehicles about every six months to help keep the intake and the injectors clean. This is the only gasoline additive that is recommended for use by some vehicle manufacturers, such as Chrysler and BMW.

Using regular gas in a vehicle designed for premium gas can reduce fuel economy and performance because the computer does adjust the spark timing based on the octane rating of the fuel as detected by the knock sensor.

However, using premium fuel in a vehicle designed to use regular fuel will not cause an increase in fuel economy or performance, in most cases.