If you want to set off an argument, especially in the Motor City, all you need to do is ask, "What would Jesus drive?"

But much as some people might want to keep faith separate from energy and environmental issues, the interfaith groups aren't going away. Despite the slogan of the car campaign, they come from many faiths. Despite the brashness of "What would Jesus drive?" they usually don't make themselves so visible. And when they're working behind the scenes, they almost always get a good reaction.

"People say, 'Gosh, I'm glad the church is involved in something I can relate to,' " said Sally Bingham, an Episcopal priest in California who is one of the pathfinders in bringing the faithful to the environment.

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