ABQjournal: Documenting Noise Helps Locate Cause

Saturday, October 28, 2000

Documenting Noise Helps Locate Cause

    DEAR CAR CLINIC: I have a 1992 Mercury Grand Marquis LS with 90,000 miles. Recently, when I brake or turn a corner I get a squeal. My brakes supposedly were checked and all is OK. What could be the problem and is it dangerous to drive the car? Thank you. — J.G., Bella Vista, AZ
    DEAR J.G.: I wish I had an easy answer for you, but there are so many different types of squeaks, thumps, rattles and clanks that a car can make. Without being able to actually hear the noise, it will be next to impossible for anybody to tell you what is wrong.
    The best thing you can do is to try to document — in as much detail as you can — when the noise appears, under what conditions it seems to be worst, and how often the noise occurs. The more information you can give to the technician, the easier it will be for him or her to diagnose this problem.
    There is always a chance that you have a brake pad that has inherent squeaking problems. The only way to repair this particular problem is to replace the brake pads with a high-quality pad — no discount pads!
    I personally have had the best luck with the top-of-the-line Bendix brand pads. These pads will not be cheap, but if this is your problem these will go a long way toward ending the noise.
    Don't forget that the rotors must be resurfaced, and the wheel bearings checked and repacked with grease and/or replaced as needed. New grease seals should also be installed at this time.
    And remember: The bitterness of poor quality will be remembered long after the price of a job well done.
    Thanks for your question. — Rick Jones, ASE master certified technician, Bosque Farms
    DEAR CAR CLINIC: I have a 1991 Mercury Grand Marquis with 98,000 miles. Recently the "check engine" light went on for a few miles, then went off. My mechanic said not to be concerned.
    A few days ago, it did it again. I stopped, turned off the motor, then started it again and it was OK.
    My mechanic says to bring it in when the light is on. Naturally, the last time it happened was on a Saturday evening at 7 p.m. I'm 76 and planning a trip out of town. Any advice? — F.N., Taos
    DEAR F.N.: The technician that told you there is most likely nothing seriously wrong with your car is probably correct.
    The reason for the "check engine" light coming on is not always easy to diagnose on Ford products. Ford did have problems with their EGR (exhaust gas recirculation) systems for a number of years. This is an important part of the car's emissions controls and when it is not working correctly the car's on-board computer will detect the problem and turn on the "check engine" light.
    When the EGR system is malfunctioning, often the light will come on but you won't feel any difference in the way the car performs.
    There are more than 60 different fault codes that will turn on a "check engine" light. Why your car's light is coming on can only be assessed by an experienced technician with the proper equipment.
    I wouldn't get too excited as your car will start to run very poorly if something serious is wrong. So I would say take your trip since it will most likely do more good than harm to your car.
    Thanks for your question. — Rick Jones, ASE master certified technician, Bosque Farms
    Answers in this column are provided by Albuquerque-area automotive service shops. Got a question about your car, truck, van or RV? Describe your problem (please be brief!) and fax it to (505) 823-3994 or mail it to Car Clinic, Albuquerque Journal, P.O. Drawer J, Albuquerque, NM 87103.