Q: What is your opinion regarding the rapid introduction of "driver aids," from simple warning systems up to but not including driverless cars?

A: Thanks for your question. I always enjoy the opportunity to climb up on my soapbox and espouse my opinions on things automotive. Having spent a fair amount of time driving motor vehicles with most of the latest driver aids, one thing is absolutely clear. The federal government, insurance companies, safety groups and carmakers believe that the majority of motorists desperately need these electronic "nannies" to survive our highways.

Sadly, they are not wrong. Modern passive and active safety systems have significantly reduced the injury/fatality rates, but not crash rates. We're still colliding with other motorists and solid objects at unacceptable rates. Could there be any other reason for the tremendous effort to develop driverless vehicles?

In my humble opinion, most motorists would be safer traveling in a driverless vehicle programmed to recognize, identify and respond to pending threats instantly and automatically.

Sadly, the majority of humans cannot and do not. Daily routines, distractions of all types, multitasking, comfort and ease of operating modern vehicles — all contribute to allowing drivers to lose focus on driving. This delays recognition and response to impending threats, directly contributing to crashes.

In that respect, all driver aids are worthwhile. ABS, TCS, stability control, lane departure and closure rate warnings and the like are active safety systems with the role of full-time watchdogs, waiting to spring into action when you get in trouble.

Am I eager to ride in an automated, driverless car? No, I enjoy driving and have never liked riding without control. However, the only times I ever turn off the "nannies" in my 600-plus-horsepower Corvette is on the race track. On daily drives, they're all armed and ready.

Q: I have a 2005 Subaru Outback with 160,000 miles. Last summer the "Check engine" light began coming on, seemingly randomly. Our mechanic diagnosed a faulty oxygen sensor, a surprisingly expensive fix. Less than a year and 5,000 miles later the "Check engine" light is on and off again. We notice no difference in power or mileage, only the lack of cruise control. Should we pay to have the diagnostics and (possibly) sensor replaced again?

A: While it may seem that the "Check engine" light is coming on for the same reason, you can't assume this. There are hundreds of DTC fault codes that can trigger this light. My suggestion is to stop by an auto parts store that offers free DTC code checks with a scan tool. If it is the same O2 sensor again, perhaps it's covered by some type of repair warranty.

The lack of cruise control function may indicate the DTC triggering the light is an issue with the cruise control inhibitor switch, brake light switch or some other component that would default the cruise to a fail safe mode.

Q: Our two vehicles have always had regular 5,000-mile maintenance checks performed. Although we don't drive on dirt roads, it seems we're shown air filters that need replacing more frequently than recommended — every 30,000 miles or 36 months. Are we being shown OUR air filter, is the condition of our air filter being exaggerated or should we be replacing our engine air filter more frequently than 30,000 miles or 36 months?

A: Next time, watch the service being done on your vehicle. Follow the air filter's "chain of evidence" from the filter housing to your eyes. Or check the filter yourself before the next maintenance — does the filter they show you look like the one you inspected?

The air filter needs to be replaced when it's dirty or the recommended replacement interval — whichever comes first. For DIY-ers, tap the filter, upstream side down, on the palm of your hand. A handful of dirt confirms it's time for a new filter.