Q–I read about the failure of a compass to perform properly (Motormouth, Oct. 5). The compass I put in my 1991 Chevrolet Caprice pointed only north. Readjusting the compensators and repositioning the compass were ineffective.
I returned it to Airguide and received a replacement, which acted just like the first one. I even tried a Hall effect version, but all I learned was that my hood ornament was north of the driver’s seat. Suggested corrections include everything from degaussing to exorcism, but no practical fix has appeared. D.H., Chicago
A–We’d like to give you some direction, but even the technical folks at Airguide were at a loss. According to the spokesman, digital and electronic instrument panels create such strong magnetic fields that no ordinary compass will read true. He said this has particularly been a problem with the Caprice and Impala and some Ford pickups.
Q–I have had occasional problems starting my ’93 Ford Ranger (43,000 miles) when it is cold with heavy moisture in the air. I have taken it to the dealer several times to no avail. They replaced the battery once, did nothing a second time and replaced the starter wire on a third occasion. By the way, the engine has started without problems on several occasions when the temperature was way below zero, but there was no moisture in the air. J.D., Chicago
A–When you have a no-start problem, does the engine spin normally when you crank the starter? If so, we suspect a problem with the ignition system. The voltage can escape from the spark plug wires and jump to the nearest metal parts on the engine, robbing the spark plugs of the juice necessary to jump the gap between their electrodes. Repeated attempts to start the engine will run down your battery.
Does your starter crank slower than normal in wet weather? If so, we suspect high resistance in the starter, solenoid or cables leading from the battery. Weak or corroded ground connections should be considered.
Q–I have a 1997 Pontiac Grand Am GT coupe. The front-end seems to have a squeak/clunking noise when I go over bumps. The sound is more noticeable on cooler mornings. The joints are sealed at the factory so lubing is not possible. What could be wrong? A.H., Chicago
A–Squeaking and clunking are seldom the result of poorly lubricated ball joints. The most likely suspects are sway bar bushings, MacPherson strut mounts or bearings or spring insulators. However, we suggest you fully describe the symptoms to your service manager rather than offer suggestions for repairs.
Q–My 1996 Ford Crown Victoria occasionally stalls when I am slowing down to make a stop or turn, but usually only when the gas tank is three-quarters or more full. Also there is a popping sound in the rear, which I have been told is a gas-venting problem that they can’t figure out. Has anyone else had this problem? J.S., Calumet City
A–We haven’t heard from any other readers regarding the popping, but have heard of many stalling problems. There has been a problem with the idle air control motor, which keeps your car idling properly when you take your foot off the gas–such as when slowing down to stop or turn. The fact that yours stalls only when the tank is nearly full has us a little puzzled, however. We can only speculate that, if a vacuum is created in the tank, it might reduce fuel flow.
For diagnostic purposes, leave your gas cap a bit less than snug when your gauge reads about three-quarters. (Don’t do this with a full tank and do not leave it loose for long because of the pollution fuel vapors cause.) Because most gas caps have check valves that allow air to enter the tank as fuel is consumed, a new fuel cap may be the solution.
Q–I have a 1995 Chevrolet Lumina with a 3.1-liter V-6 that is noisy when I start it cold. The dealer replaced the serpentine belt, which did not get rid of the noise. The next time I took it in, they said everything was normal. Since then, I have found an article that refers to GM service bulletin 57-61-24, which defines the problem.
In one of your past columns, I also saw a reference to piston slap. Can you suggest any way to get the problem fixed? I am worried that I will have an engine problem and the warranty will have expired. B.J., Chicago
A–We read the clipping you enclosed and agree that the problem is likely excessive clearance between the wrist pins and pistons–not the same as piston slap but with a similar sound. Keep after your dealer until you get satisfaction, call the zone office and the toll-free customer service number. Be persistent.
———-
Bob Weber is an ASE-certified Master Automobile Technician. Write to Motormouth, 17717 Silcott Springs Rd., Purcellville, Va. 20132. Send e-mail with name and hometown to motormth1@aol.com. Answers are supplied only through the newspaper.
