Q. I have a 2008 Ford F-150 with a 4.6-liter engine. The truck has only 4,000 miles on it but already seems to have a problem. At certain times when I push on the gas pedal, I hear a hissing noise. The dealer replaced the power brake booster but the problem still exists. Is this a normal condition or a problem?

A. I have driven many Ford F-150s and never heard a hissing noise. The dealer wouldn’t have replaced the brake booster unless they heard something as well.

Many items under the dash of your truck are vacuum controlled and it is possible one of these vacuum lines or switches is faulty. One tool many shops are using to find vacuum leaks is a smoke machine. A technician will fill the system with a synthetic smoke and wait to spot the leak. At this point, see if the dealer will perform this test as well as look for any pertinent technical service bulletins that may help find the hissing noise.

A hybrid may suit you

Q. I am looking for an eco-friendly choice for a family car. I am hoping for electric, solar or a multi-fuel vehicle that would be kind to the environment.

A. Currently there are no solar, and very few electric cars for sale in the United States. Tesla Motors is a company that is selling an electric car in California. It is an electric roadster with a price tag of nearly $100,000.

In 2010, Chevrolet will be selling a very advanced hybrid called the Volt. This car is capable of running on pure electric power for 40 to 60 miles. As the battery starts to deplete, there is a small gasoline engine that can recharge the battery. This combination will give the Volt a long range with nearly zero emissions from the tailpipe.

Although there are many cars that can run on gasoline or E85 (fuel that’s made from 85 percent alcohol), currently there isn’t a local fuel station that sells E85.

If you are looking to make a purchase in the near future, take a look at the hybrids. Available now or very soon, are the Toyota Prius, Honda Civic, Insight, Nissan Altima and Ford Fusion.

projocars@projo.com