Auto Doctor: Why squealing brakes are seemingly more common
Dear Doctor: I own at 2007 Nissan Altima. The Tire Pressure Monitor System light stays on. I checked the air pressure and increased the air pressure to 36 pounds, but the light remains on. The dealer said the battery in the actual monitors inside the rims are dead and that the monitors need replacement at a cost of $800. I asked the local shop if they can shut the light off and they said it's against the law to alter the TPMS. What can I do? -- Betty
Dear Betty: I like the idea of tire pressure monitors. What I don't like is all the frozen tire valve stem caps and valve cores, as well as the cost of monitor replacement, and the short life of the monitor batteries. There are aftermarket companies that sell universal sensors for less money and can be programmed for 90 percent of today's vehicles. During cold winter months you will find the air pressure may need to be set a few pounds higher to keep the TPM light off.
Dear Doctor: I have a 2002 Toyota Camry Solara V-6 with 71,000 miles. I am experiencing a mushy, low brake pedal. I had the brakes bled and it seemed to get a little, but that didn't last too long and it returned to being a little lower and mushy. I had everything replaced in the rear wheels; new rotors brake bands the whole works. Can you help me out? -- George
Dear George: This is an all-too-often problem seen on a variety of vehicles with disc brakes. The number one issue is sticking or frozen caliper slides. I find many frozen front brake caliper slides on Toyota vehicles and frozen rear parking brake pivots on Toyota trucks. Have your technician remove the calipers and check the slide bolts.
Dear Doctor: I have a 2006 Chevy Silverado 1500 that's great, except for the gas mileage. I'm looking to improve highway mileage and came across this item by FuelSmart. It's an inline module for the fuel injectors that disables some of them during highway speeds, like the newer trucks have. I was wondering if you have any knowledge of this product. -- John
Dear John: There is no magic plug-and-play product that will produce a big gas mileage increase. If gas mileage increases were this easy, then the big car companies would be in it, as well as the company making these claims. No, I have not tested the product.
Dear Doctor: I have two problems with my 2004 Chevy Tahoe. Over the past six months the heat has come on, by its own volition, while we have the a/c running. After turning the car off and then back on, everything was OK. Second, we were on a long trip when after 90 minutes of driving the oil gauge dropped to zero. I pulled off at the next exit, turned off the truck and checked for oil leaks, but found nothing. When I restarted the oil pressure was OK and remained so for the rest of the trip. What do you think? -- Brad
Dear Brad: Your SUV is a great vehicle, however, there might be a problem with the dash cluster. There have been many faults with dash clusters on a variety of GM trucks and SUVs. The average cost of the dash cluster repair/service is $300 - $400, depending on the service repairs needed. As for the unwanted heat, the most common heater a/c control problem is an electronic blend door actuator.
Dear Doctor: Why do I hear so many cars on the road today with brake squealing when coming to a stop? Also, why do the front wheels on a lot of cars turn black and some brown? -- Linda
Dear Linda: The brake squeal can be from glazed brake pads and rotors, inexpensive, cheap brake pads, brake pads that are missing related hardware of sticking to the calipers and caliper slides that also stick. Another possibility for squeal is rear brakes that do not contribute to stopping when the brakes are applied. Some brake pads have wear sensors that also squeak when the brake pads wear down. Regarding black/brown color on front wheels, it's brake dust. Some brake pads will have less brake dust than others. The original factory, and good quality ceramic pads, seem to give off the least amount of dust. -- Junior Damato, Motor Matters
Junior Damato is an ASE-certified Master Technician. Email questions to firstname.lastname@example.org. Mail questions to: Motor Matters, PO Box 3305, Wilmington, DE 19804