I own a 1990 Lexus LS 400 with 145,000 miles. I recently had the front struts replaced because there is a loud noise when hitting bumps. The noise continued. I went to another shop, and they said the brake pads were floating and causing the noise. What is your opinion?

QUESTION: I own a 1990 Lexus LS 400 with 145,000 miles. I recently had the front struts replaced because there is a loud noise when hitting bumps. The noise continued. I went to another shop, and they said the brake pads were floating and causing the noise. What is your opinion?


ANSWER: To check a brake pad or caliper bang is simple. While driving over the noisy, bumpy road, simply hold a small amount of brake pedal pressure while traveling over the bumps. If the noise is gone, the problem could be as simple as a brake pad or caliper noise. A big overlooked part of the front end is worn sway bar links and bushings that will create rattles and banging over bumps. This is true for both front and rear suspension systems. Upper strut mounts as well as a body or frame rattle could also be an issue.


QUESTION: I leased two Chevrolet Malibus prior to buying a new 2005. Neither of the older Malibus had a gas mileage problem. My current gas mileage, mostly city, is 13-14. This is both my pencil and electronic in-car computer mileage average. I went back to the selling dealer service department and they said wait until the car reaches 8,000 miles. I contacted GM and they referred me back to the dealer and would not discuss my complaint. I have been a faithful Chevrolet buyer for years, and this could be the last time. GM even ran a full-page ad in the paper bragging about their gas mileage, 32 highway, on the Malibu. Please advise.


ANSWER: You are not the first reader to complain about poor gas mileage. To set the record straight, city driving gas mileage will vary a lot. To be fair, you need to drive the car on the highway for 70 miles or so to get an idea for gas mileage. Just driving in the city, combined with the engine not at operating temperature, will definitely lower fuel mileage. The second part is if there was a rich condition the computer would set a check engine light for a rich condition. Engines do need 5,000-10,000 miles to break in.


QUESTION: I own a 1997 Mercedes C-230. Over the last five months, approximately every three or four weeks, the engine would die out on the parkway between 50 to 60 miles per hour. It feels like the engine is running out of gasoline. The stalling seems to happen with the gas tank half full. Each time it happens I add about a half gallon of gas to the tank and the engine starts up. I was told this is an intermittent problem and they cannot locate the problem. This does not make sense to me. Can you help?


ANSWER: How simple can it be? The shop needs to hook up a fuel pressure tester and send you on your way. We need to see if the problem is low or lack of fuel pressure. If it is lack of fuel pressure, the next step is hook up a volt meter to the fuel pump, both positive and negative. Next hit the road again. You will have to have someone monitor the fuel pressure and voltage. This is the first step on your road to recovery.


Junior Damato writes regularly about cars. You can send questions to him care of the Old Colony Memorial, 182 Standish Ave., Plymouth, MA 02360, or e-mail ocm@cnc.com.