LOS ANGELES — Would you buy a Honda just because some guy with a Honda logo on his shirt helped unload your grocery cart?

Honda figures you might. For five months, area dealers have been dispatching blue-shirted crew members to pump gas at service stations, pass out popcorn at movie theaters and offer aid in supermarket parking lots. One Saturday in Pasadena, every parking meter on Colorado Boulevard was plugged and covered with a "Helpful Honda" hood that said, "It's On Us."

You might think it would be futile to squeegee a windshield for someone who isn't even thinking about buying a car, but research shows that the kinds of stunts Honda is pulling can work.

"Personal touch is a very powerful way of creating a brand message," said Kelly O'Keefe, executive education director at the Virginia Commonwealth University Ad Center.

A lot of car companies are resorting to what's known as engagement marketing: throwing parties and sponsoring concert series and wine tastings, often without an automotive vehicle in sight.

The Southern California Honda Dealers' campaign, created by Secret Weapon Marketing of Santa Monica, is paired with television spots that show the incredible lengths to which dealers will go to lend customers a hand, in one instance by donating a kidney.

"The strategy is to bring the campaign to life on a personal level with people," said Dick Sittig, Secret Weapon's creative director. "Maybe they'll think, 'What has my car company done for me lately?' "

Toyota Motor Corp.'s Scion brand pioneered auto engagement marketing in 2003 by sponsoring Scion Metro concerts, headlined by such hip-hop artists as Wu Tang and Little Brother. The idea was to introduce Scion, a new brand, to young consumers. Jeri Yoshizu, Scion's sales promotion manager, said it succeeded: The Scion has proved popular with buyers under age 35, and sales were up 11 percent last year from 2005.

Toyota has taken the lessons learned from the Scion campaign and applied it to other brands. To promote the Yaris, it kicked off the "Free Yr Radio" campaign in April, sponsoring indie bands that play in Urban Outfitters stores. The concerts are advertised via e-mails that only briefly mention the Yaris. Toyota's Lexus brand sponsors wine tastings and cocktail parties that are targeted at a more upscale audience.

"There's a dialogue that needs to happen beyond the limitations of the 30-second spot and the Web page," said Bruce McDermott, head of Saatchi & Saatchi's Brand Integration Group in Torrance, which works for Toyota.

And if the youth who show up at the Urban Outfitters concerts aren't in the market for a vehicle?

"If you're not on their shopping list," McDermott said, "you're not going to make it on their buy list."

The auto industry has embraced engagement marketing because many TV commercials for cars, and cars themselves, are so similar, said Eli Portnoy, the Los Angeles-based founder of Portnoy Group, a brand consultancy. "In automotive advertising, you can take the nameplates off and a lot of it is the same."

And there's so much advertising for cars on TV — it's nearly impossible to watch a show without hearing about acceleration in zero to 60 seconds, V-6 engines, side airbags and APR financing — that it can be numbing.

Engagement marketing can help break through the clutter, though there's a danger of losing customers, Portnoy said, if a dealer doesn't also promote a vehicle in the traditional way.

But seriously, what difference can a Helpful Honda deed make?

At a gas station in Inglewood, where a crew was filling up the tanks of Hondas and cleaning windshields for everyone else, some motorists looked on wistfully as Honda owners drove away with $40 or more of free gas. One woman stuck her head out of the window of her Volkswagen and yelled: "I think I'm going to buy a Honda now!"