That great deal you got last month of a shiny new car has turned sour. You're afraid to turn the key in the ignition for fear something else will go wrong, and you've been back to the dealer so many times you and the service manager both are about to explode at the sight of each other. What to do?

You can write the Better Business Bureau, start a letter exchange with the manufacturer. You can call a lawyer and sue the .

Or, says Gerry Murphy, executive vice president of the Automotive Trade Association, National Capital Area, you might want to call AUTOCAP (Automotive Consumer Action Program). "If you want to go to a lawyer, you can do that, but I think any consumer agency will tell you to take your free shot first."

AUTOCAP is an association service provided member dealers and a public service available free to any consumer who has a question or a problem with a new-car dealership transaction (including used-car purchases).

AUTOCAP was started in 1973 by the National Automobile Dealers Association in conjunction with the White House Office of Consumer Affairs. There are 45 or so chapters around the country, operating through dealer associations.

Although the service is funded by member-dealers, "By the same token," says Murphy "we have consumer panels that are the ones that actually decide the cases." The panels are made up "equally of consumer professionals from the community and auto-dealer members."

Warranty complaints make up the majority of AUTOCAP's cases. "We very rarely have a so-called lemon situation come up," says Murphy. Typical cases involve "the consumer who has bought a car and he's got some problems in his own mind or some real, substantive problems. In either case, we'll become involved in it and work with him and the dealer and the manufacturer to get his car repaired."

Most of the cases are resolved, Murphy says, on the staff level and don't even make it to the panel although the panel oversees the staff's handling of cases. "They audit our files every month." Case mediation generally averages three weeks.

"We bring a lot of free expertise to bear on the consumer's problem," says Murphy. "We've got lawyers and technicians who sit on this panel and evaluate the problem."

Although dealer members have no contractual obligation to abide by the panel's recommendations, "Our success rate," says Murphy, "speaks for itself. We've had only one instance in 10 years where a dealer didn't go along with us."

The panel has never had occasion, he says, to order a car replaced or refund the purchase price. AUTOCAP's 8-out-of-10 resolution rate, says Murphy, "suggests there aren't really a lot of quote-unquote lemons out there."

The dealers, Murphy points out, understand that resolving consumers' complaints "is something that's in their business interests. As far as the consumer is concerned, he doesn't waive any legal rights. He can go to court or another agency or whatever he wants to do," if he disagrees with the panel's ruling.

For more information on AUTOCAP, or to register a complaint, call 657-3200.