Q: On an all-wheel-drive (AWD) vehicle, do front brake pads wear faster than rear brake pads?

A: Yes, but it has nothing to do with AWD. The front brakes on most cars wear faster than the rear brakes. Roughly 80% of the stopping power is supplied by the front brakes. You probably have noticed that the front of the car dives a little under hard braking. At the same time, the rear of the car raises, taking some of the weight off the rear wheels.

Breaking brakes

Q: When my dad was in his 70s, he would drive with one foot on the brake pedal at all times. I see quite a few drivers with brake lights glowing as they drive 45 miles per hour on the freeway. I'm not saying that these drivers all are elderly, but regardless of their age, I can only imagine the damage to a brake system if that pedal was being pushed hard enough to constantly engage braking.

A: Resting your foot on the brake pedal not only causes wear and tear on the brakes, but it also causes the engine control management system to drop out of closed loop operation. The computer thinks the car is stopping and the engine power is no longer needed.

Gasket grief

Q: Two weeks ago, a writer questioned whether it was wise to run out the gas of lawn mowers and snow throwers when they were stored for the season. You suggested adding Stabil (or its equivalent) to the gas instead. While I agree with that, one thing you didn't mention was that some of the carburetors on the small gas engines have gaskets or diaphragms that go bad if they are exposed to air for any length of time.

A: Yes, the gaskets and diaphragms can dry out and fail, but that's not as much of a problem as it used to be. Modern components are less prone to that.

Pesky warning light

Q: Recently my fuel pump needed to be replaced. The mechanic also replaced one section of the fuel line because of an updated design change. The day after I picked up the car, the check engine light went on. Codes say it is the gas cap, but repeatedly tightening the cap hasn't helped. The mechanic turned off the check engine light, but it was back on within a week. Is there any chance this is related to the fuel pump and fuel line replacement? Or is it all just coincidence?

A: Have you tried a new gas cap? Any leak in the evaporative emissions system, including the cap, will trigger the check engine light. If a new cap doesn't help, ask your mechanic to check all the connections he might have disturbed.

Bob Weber is a writer, mechanic and ASE-certified Master Automobile Technician. His writing has appeared in automotive trade publications, Consumer Guide and Consumers Digest. Send automotive questions along with name and town to motormouth.tribune@gmail.com.