In October the Chinese authorities announced a new measure that may help curb the trade in Hong Kong cars: a ban on the registration of vehicles with the steering wheel on the right side. In Hong Kong, people drive on the left and so cars have the steering wheel on the right, while it is the other way around in China.

In theory, the ban would make Hong Kong vehicles useless in China. But a similar rule was introduced in 1988 and never put into practice, and it is too early to tell whether the new ban will be enforced more rigorously.

"It is hard to get a new car on the road if it has right-hand steering," said a taxi driver in the southern Chinese city of Guangzhou who owns a second-hand Hong Kong van with the steering column on the right. "But if you've got connections with the police, you can get around the new rules." Stopping Theft of the Lexus

Perhaps the most innovative approach to deter thieves has been taken by Crown Motors Ltd., the distributor in Hong Kong for Toyota.

Neither Toyota nor Crown will sell cars or spare parts to China for the Lexus model, and in May Crown announced that even in Hong Kong it would sell parts only to legitimate owners of a Lexus.

Crown Motors also took the unorthodox step of advertising in Chinese newspapers, reminding people that the Lexus is meant to use only unleaded fuel and will break down after fewer than 20,000 miles if it uses leaded gasoline, the only fuel available in China.

"We haven't had a single Lexus stolen in the last few months from Hong Kong," said John Haines, the managing director of Crown Motors.