Q: The on-off indicator for the passenger-side air bag in my new Toyota Camry is erratic. My wife weighs under 100 pounds and the indicator takes anywhere from one second to two hours to light up when she's in the seat. We think this is a serious safety problem. Can you help?
A: You're right, it is a safety problem. Front passenger seats each have a sensor that detects someone's presence in the seat and lets the air bag know, so it will deploy in case of an accident. Without a go-ahead from the sensor, the passenger-side air bag won't operate. That sensor should unhesitatingly detect even a lightweight person. Your car appears to have a faulty sensor, in which case the air bag isn't getting the message, or the problem could be a defective on-off indicator. It's important to be sure you have a fully functional passenger-side air bag system. Since the car is new and under warranty, go back to the dealer and have it repaired.
Q: At 130,000 miles, the camshaft in my 1997 Chrysler Town & Country minivan broke near one of the rear cylinders. I have maintained the van regularly, taking it for service every 5,000 miles. The two technicians who inspected the engine both said such a break is very unusual. Do you have any ideas about what may have caused it and how I can prevent a recurrence?
A: At risk of sounding like Little Sir Echo, I'll agree that camshafts hardly ever break. Two possible explanations for what happened come to mind, both long shots: First, a bearing might have been inadequately lubricated, causing excess heat. Second, metal fatigue combined with an inherent flaw in that particular camshaft may have resulted in the failure. Whatever made the camshaft break, it's unlikely to happen again—in this or any other car you own. A camshaft opens valves in each cylinder at just the right moment to let air and fuel into the combustion chambers and exhaust gases out. It's driven by the crankshaft through a belt, chain, or gears. Despite its hot and hectic existence, it usually lasts the life of the car.
This article was first published in November 2006. Some facts may have aged gracelessly. Please call ahead to verify information.