Traffic is stopped on the interstate. Ahead lays a construction zone with a posted speed limit of 55 mph. Nearby, a meter that reads the speed of passing motorists reads, "Your speed" followed by ... nothing. It's shut off. We aren't moving anywhere. What a tease.

It's then that I realize why gas-electric hybrids are such a good idea. The gas engine shuts off as the vehicle comes to a stop, restarting when you hit the accelerator. So even if your frustration is growing as you sit in traffic, you can be comforted that the hole in the ozone layer is not. At least, not because of your vehicle.

Ford Motor Co.'s hybrid system, like Toyota Motor Corp.'s, uses an electric motor to propel the vehicle up to 40 mph, sometimes in tandem with the gas engine. At highway speeds, only the gas engine runs.

The electric battery pack that powers the electric motor never has to be plugged in. It's recharged by the gas engine and energy captured during deceleration.

It's an ingenious solution; albeit one that adds a few hundred pounds to the vehicle. A diesel engine would weigh less and return similar or superior mileage, but most Americans find diesel, not to mention drivetrain, to be a dirty word.

So we have hybrids. And Dearborn-based Ford's system, developed in-house by Ford, has been revised and greatly improves the Ford Escape Hybrid and its identical cousin, the Mercury Mariner Hybrid.

The four-cylinder engine has been enlarged from 2.3 liters to 2.5 liters. Horsepower jumps by 20, now rated at 153. Combined with the electric motor, the vehicle generates 177 horsepower, six more than the non-hybrid four-cylinder model. Yet the Hybrid returns superior mileage: 34 mpg in the city, 31 on the highway versus 22 in the city and 28 on the highway.

Those ratings are for the front-wheel-drive model; all-wheel- drive models use slightly more gas: 29/27 and 19/25, respectively.

The Hybrid's horsepower is fed through a continuously variable automatic transmission, also known as a CVT.

Rather than having a conventional transmission's five or six fixed ratios, the CVT constantly varies its ratio to conserve fuel. The downside to CVTs is their sluggish response when asking for more power. But this one is an exception. And when you need it, there's more than enough power to deal with the pokey parkway grand prix.

Ford has switched to electric power steering, and although road feel doesn't seem to be affected, there isn't much. Still, it seems tighter this year and is nicely weighted.

The suspension has been retuned as well. A new rear stabilizer bar and revised shock absorber tuning deliver a more refined ride. It feels a lot less crude, and sharp impacts are muted. The Escape is almost luxury-car quiet. Only the engine's moan gives away the vehicle's price point.

Safety gear includes antilock brakes and electronic stability control.