Boston — Massachusetts is trying to add a new twist to ''lemon laws,'' statutes that require automakers and dealers to repair or replace defective new cars quickly. Within the past two years at least 19 states have adopted such laws.
Similar measures are under consideration in more than a dozen other states.
But these laws don't cover used cars, a situation of increasing lament to used-car owners and consumer activists across the nation.
An estimated one-third of all used cars sold in Massachusetts, for example, have a major defect unknown to the purchaser at the time he or she buys the car, according to a study by the Massachusetts Public Interest Research Group (MassPIRG).
''Used-car buyers are tired of being taken for a ride,'' asserts MassPIRG attorney Jody Forchheimer.
Buoyed by its successful 1983 push for a new-car lemon law, MassPIRG is now lobbying heavily for passage of what is believed to be the most comprehensive measure of its kind, mandating car dealers to provide limited warranties on all preowned autos sold.
The proposal, similar to ones being discussed in several other states, including Arizona, Connecticut, and New York, is patterned somewhat after a more than decade-old Wisconsin used-car disclosure law.
But unlike the Wisconsin law, under which some 2,500 complaints a year are filed, the Massachusetts bill would require the seller to fix, at his expense, whatever was wrong and if unable to do so within a specific period, to refund the customer's money
In the Massachusetts legislation, the warranty of fitness would cover the performance, soundness, and safety of the vehicle.
Private sales - those between friends, neighbors, or coworkers - would be exempt.
Such transactions account for about 37 percent of used-car purchases in the New England area.
Autos sold for $1,000 or less would have a 20-day warranty, those from $1,000 to $5,000 a 90-day warranty, and over $5,000 a 180-day warranty. Within these periods, the seller would be allowed three attempts to correct the defect at no charge to the owner, providing that the defect was not disclosed in writing, along with the cost of necessary repair, at the time of the sale.
As in Wisconsin, dealers would provide car buyers with a list of all major parts and accessories indicating their condition. The seller, whether the small corner used-car lot or a large dealership, would be responsible for checking out everything from brakes and headlights to steering column and engine, noting whatever problems there might be or could be expected during the warranty period.
The buyer also would be advised in writing how the vehicle had been used by its previous owner - whether as a pleasure car, demonstrator, or lease auto.
In Wisconsin more than 60 items are listed on the disclosure form the purchaser gets along with the car. If the information is falsified, the state can revoke the dealer's business license.
Complaints concerning possible violations of the used-vehicle disclosure law are investigated, and, if necessary, hearings are held to determine whether there was fraud, explains Chuck Supple, consumer specialist for the Wisconsin Auto Dealers Licensing section. He adds, however, that since there is no warranty at issue, used-car sellers can't be forced to repair defects or give refunds.
The MassPIRG statewide survey of used-car purchasers found that one-fourth found defects cropping up within the first month, with half of the problems labeled serious.
MassPIRG interviews with disgruntled used-car buyers spotlighted heavy repair bills and potentially dangerous defects
''Lemons'' are no respecters of price, Miss Forchheimer says, adding that there is often little relation between the price of the car and and the extent of defects.
Evan Johnson of the National Center for Auto Safety in Washington, D.C., foresees increased interest in used-car lemon laws in coming years.
Prime opposition to the proposal is coming from the Massachusetts Auto Dealers Association (MADA). Its leaders contend that the law is not needed and would only drive up used-car prices.
The legislation would duplicate rights consumers already have through existing fraud and warranty laws, Jeffrey Hodgdon, the MADA president told a panel of state lawmakers.