Would you buy a used car from yourself?

The economists who are not taking the Fifth Amendment for their past crimes of prophecy are predicting that this will be - well, couldm be - the Year of the Car.

The automobiles collectively coughing smoke on the American highways are said to average an age of seven-and-a-half years. How long, the economists ask themselves, can these poor excuses for chariots of fire chug on?

And so, if in January - or even on Jan. 10, say - more cars are sold than on Jan. 10, 1982, the end of the recession will be proclaimed, with new wheels leading the way.

We're all eager to have the good times roll, whether it's automobiles or new construction or hula hoops that head the parade. At some point, certainly, the new-car customer of the '80s will finally appear, like a long-lost prodigal son. But will thzoo gver be quite the same as they were?

We have a feeling that the mystique of beat-up-and-secondhand has replaced the mystique of shiny-new in the hearts of the American car owner.

People have discovered that rusty dents and an unpredictable backfire now and then give a vehicle a prancing individuality it never had a chance to acquire when it was traded in every two years at the sign of the first splutter.

One becomes fond of an erratic old car the way one becomes fond of a black sheep uncle whose unsurpassed waywardness fills one simultaneously with pride and shame.

When someone borrows your car, even for just a run to the supermarket, a sense of decency obliges you to make out a warning list of character flaws:

Totally irresponsible about starting in parking lots.

Absolutely scandalous on the hills.

Not to be trusted for sudden braking.

Winks with the left headlight after dark.

What do these cranky old codgers have in common with the glossy young models described in road tests, and severely faulted for having too small a glove compartment or an inconveniently located defroster switch?

Most of us have traded in our old-time perfectionz MoO the new art of survival. We ask just two questions: Will it start? If so, will it go?

And if it does neither with regularity, we make a legend out of that, sitting around repair shops by the hour, swapping yarns about lemons that break down only on country roads at night or in expressway tunnels at the rush hour.

What good camaraderie the fellowship of failing engines can lead to!

In fact, there seems to be a different attitude toward The Machine in general. Most of us have theorized at being master - and practiced at being slave - to earlier cars, not to mention a dishwasher or two. We've been through the Faustian power game, and few illusions can be left about the perfect pushbutton at the masterly fingertip. We're more likely to treat our four-wheeled eccentrics as human, the way the first automobile owners did when they gave their cars names, like Old Betsy, and expected almost nothing from them.

This may constitute the best possible preparation for the Age of the Robots, when people will have the personality of an overhead cam and only computers will retain a smack of Dickensian character. Remember Hal in ''2001''?

At any rate, given the choice of learning how to replace an overhead cam or buying another set of flares, we're on our way to the hardware store right now - with a trunkful of orange ''Help!'' signs and a heart full of forgiveness in case Old Betsy doesn't make it.