Q: I’ve been noodling this for a long time. When we fill up our Escape, the “miles to empty” number varies wildly. One time it will read 325 miles, the next time 295, then 306, etc. If we’re filling the tank with about the same amount of gas, why are these numbers so skewed?
Steve Dini, San Jose
A: Good question, so I turned to Jeff-the-Roadshow-Car-Man, who says:
“This is largely based on usage and history, both recent and longer-term. As an example, I tow a trailer with my Ford truck and my distance to empty varies widely depending on how long and how much I’ve been towing. If I’ve been driving on the freeway without the trailer, it can show a distance to empty of over 900 miles. If I’ve been towing plus driving uphill, I’ve seen readings lower than 500 miles.
“In the case of Steve’s Ford Escape, his distance to empty is calculated with an algorithm that takes into account his current mpg, his average mpg and his recent several mpg readings. This can vary widely.”
Q: Thank you for the history lesson on the great carpool experiment of 1976 on the Santa Monica Freeway. You correctly described the situation.
I was living and working in Palm Springs and occasionally was required to travel by car to Los Angeles on The 10 (sorry) toward Santa Monica, roughly 105 miles. I had to leave so early that it was often better to fly on a little commuter airline puddle jumper into LAX and then rent a car.
However, readers are justified in our confusion about “adding” toll lanes to carpool lanes. It could have been unclear language of Caltrans press releases saying “new.” Or the way that the media translated that information. Whatever it was, we were left with the false impression that an entirely new, separate lane would be constructed, not converted. We wrongly believed Caltrans had learned the lessons of 1976.
Robert Whitehair, San Mateo
A: In 1976, Caltrans converted a regular lane into a carpool lane on Interstate 10 from downtown Los Angeles to the ocean. Taking away a lane each direction on a jammed freeway when there weren’t many carpoolers was a disaster. It was reversed after five months, with the state deciding it would never again make the same mistake. But in 2008, the Legislature approved converting existing diamond lanes into express lanes that drivers can use for a toll. It did not get much attention at the time, but it is now.
Q: Why would we support express lanes? Sounds like time for a ballot proposition!
Jim Sutton, Saratoga
A: There are no plans for a ballot measure.
Join Gary Richards for an hourlong chat noon Wednesday at www.mercurynews.com/live-chats. Look for Gary Richards at Facebook.com/mr.roadshow or contact him at mrroadshow@bayareanewsgroup.com or 408-920-5335.
