Bob Potter wasn't looking to unload his trusty 1985 Volvo, which had 188,000 miles on the clock and a smattering of dents, dings and rust along its boxy beige body.

Despite its age, the car, which had been in Potter's family since it was new, ran pretty well.

But when a friend at work told him about the government's new "cash for clunkers" program, Potter changed his mind.

On Monday, the Marietta man traded in his Volvo for a loaded cherry-red 2009 Chevy Cobalt.

Because the new car gets better fuel economy than his Volvo, the federal government gave Potter $4,500 toward the price of the Cobalt.

That, coupled with a $2,000 rebate from General Motors and a discount from Whitmoyer Chevrolet-Pontiac, cut the Cobalt's sticker price by about $7,000 — more than a third.

"It was too good of a deal to pass up," said Potter, who had never before bought a new car. "I wasn't going to get $4,500 for my (Volvo) anywhere else."

Potter is among the hundreds of car shoppers who have descended on local dealers to cash in on the clunker program, which kicked off Monday.

The program has proven so popular here and across the nation that the $1 billion Congress approved in clunker rebates was nearly depleted by Thursday.

Lawmakers agreed Friday to pump another $2 billion into the program.

In addition to encouraging consumers to swap their guzzlers for more fuel-efficient, cleaner-running vehicles, the effort is designed to jump-start lagging car sales.

Local dealers say it's done that — in spades.

"There's definitely been more showroom traffic in the last few days, and a lot more phone calls," said Don Slavin, general manager of the Jones Honda, Acura, Pontiac, Buick, GMC and Suzuki dealerships.

"I'd say we're up by 20 percent," Slavin said.

Damian Wissler, general manager of Susquehanna Dodge/Chrysler/Jeep, said showroom traffic at his dealership has tripled this week and "the volume of inquiries is huge."

At Whitmoyer, new car sales have more than doubled since the clunker program began, said owner Dane Whitmoyer, whose Mount Joy dealership had made 15 clunker cash sales by Thursday.

"It is bringing people in, and even if they don't qualify (for the program), they're looking at cars," he said.

To participate, an owner must trade in a car that gets 18 mpg or less and replace it with a new car that gets at least 4 mpg more than the old one.

That qualifies the buyer for a $3,500 price cut on the new car.

If the improvement is 10 mpg or more, the allowance increases to $4,500.

Owners of SUVs, pickup trucks and minivans can get a $3,500 allowance if their new vehicles get at least 2 mpg more than their old ones.

That price cut increases to $4,500 if the improvement is 5 mpg or more.

In general, if a vehicle's trade-in value is less than its clunker allowance, the buyer makes out.

Whitmoyer said a customer Tuesday night traded in a battered 1985 full-size Chevrolet pickup — worth practically nothing — for a new Chevy Colorado.

The fuel economy difference between the two trucks was modest, about 4 mpg, but it was enough to earn the buyer $3,500.

"For a truck that's worth nothing, that's a good deal," Whitmoyer said.

Potter said he probably would have been hard-pressed to get $800 if he sold his Volvo, which is rated by the government at 17 mpg.

His Cobalt gets 27 mpg.

Dealers say sales of compact cars like the Cobalt and Ford Focus, along with larger sedans such as the Ford Fusion, have been surging since the clunker program started.

Their lots are filling up with old SUVs, pickups and minivans.

Those clunkers' engines must be disabled, and dealers must arrange for a salvage yard to haul the vehicles away.

The government pays dealers $50 for each transaction, and dealers can keep whatever they're paid — about $100 per vehicle, Whitmoyer said — for the clunkers.

But dealers say that doesn't come close to the cost of documenting each sale and disabling the vehicles.

"There's a half an inch of paperwork for each deal," Slavin said.

Dealers also must deduct the clunker allowance from a new vehicle's selling price up front — and wait for the government to reimburse them.

Still, the increase in showroom traffic has been a boon for an industry struggling through one of its worst years in history.

"If we move an extra 50 to 100 cars, that's an extra 50 to 100 cars we'll have to buy from the factory," Slavin said.

"If it's going to stimulate the economy, the program is worth it."

E-mail: bwallace@lnpnews.com