Future guidelines

There are several other guidelines in the pipeline including how to lodge appeals.

Such legislation is the most urgent tool to dispel and prevent possible speculation, doubt and misunderstanding of law enforcement, said industry insiders.

The forthcoming guidelines are also expected to solve problems that are hidden rules of the auto sector.

"The auto sector has a long chain from its suppliers, automakers and car dealers, and to some extent many practices have become common practices of the sector. When completed, the guidelines will expose which common practices are illegal," Shen said.

Cheng said the detailed rules would also deter those in the auto sector from looking for and taking advantage of loopholes that are not explicitly mentioned in the Anti-Monopoly Act.

In the meantime, some experts are calling for efforts to strengthen supervision, arguing prevention will be more effective than punishment.

"Price fixing has long existed widely in the industry. It is easy for several dealerships from one region to manipulate market prices, as long as they act together," said Jia Xinguang, a senior analyst at CADA.

"The priority is to supervise on a day-to-day basis, rather than launch investigation campaigns and hand out fines," said Jia.