Four years ago, Lee Iacocca, the charismatic chairman of Chrysler Corp., wrote his autobiography, and 6.5 million people purchased it. He dedicates "Talking Straight" to those "who bought my first book . . . and helped strike a blow against diabetes," the disease that killed his first wife.

In the intervening four years, Iacocca has been fired again (as head of the Statue of Liberty committee), married and divorced, and has produced a scathing attack on corporate raiders, American voters and the Republican policies of the past eight years. He unloads on the federal and trade deficits, giving President Reagan and Congress a double-barrelled blast of buckshot for failing to reduce either, and warns that unless "We The People" get a handle on our consumption habits our children (and grandchildren) will reap the punishments of our excesses.Iacocca writes in a conversational - and sometime profane - style, but one thing he doesn't do is mince words. He has little patience for incompetence - and he cites a lot of it. But rather than just rail against the storm, Iacocca is looking for ways to harness the storm clouds of doom and turn them into rays of economic sunshine.

The solutions he proposes to America's malaise - a national sales tax, compulsory two-year service for 18- to 25-year-olds and a 20 percent per year reduction in our trade imbalance with Japan - are food for thought, and he certainly presents compelling arguments. His social agenda - though he declares he isn't running for anything - allows for a single abortion, a ban on the sale of handguns and death sentences for second-offense drug pushers.

The Iacocca agenda is controversial and often blunt. But it's bound to get a hearing. If it doesn't, you can bet the next Iacocca book will be out before another four years go by.

Some sayings from Chairman Lee:

On parents: I don't understand why it is that a mother and father bring kids into the world, try to do their best to take care of them, and then the kids give them the brushoff.

On religion: I've never been a theologian in any sense, and so when I ask myself questions about (my beliefs), the answers I come up with are pretty elementary. Do I believe in a life hereafter? Yes. How do I think I got here? I don't know, but I believe the Lord sent me. . . . As I get older I think more about what comes next. I know there's got to be something else after this life is over, because I can't grasp the alternative. I can't imagine that through eternity I'll never see anyone I love again. . . "

On management style: My distillation of 42 years in the business world: (1) Hire the best. (2) Get your priorities straight and keep a hot list of what you're trying to do. (3) Say it in English and keep it short. (4) Never forget the line makes the money. (5) Lay out the size of the playing field. (6) Keep some mavericks around. (7) Stay in business during alterations (8) Remember the fundamentals.

On the press: I've got a simple solution to the shortcomings of the press: Don't believe what you read in any one newspaper. Read five. Don't swear by the New Yorker cartoons. Look at some other magazine's. Don't always listen to Dan Rather. Check out (Tom) Brokaw and (Peter) Jennings, too. Now and then when you don't like something you've read, dash off a letter to the editor. You are the ultimate deterrent to a stupid press.