Frits Bolkestein, the liberal EU internal market commissioner, is determined to launch the proposal before his term in office expires on October 31.
Carmakers have fought a lobbying campaign against the European Commission's plan to open up the market for replacement spare parts such as doors, bumpers and windscreens, to allow independent manufacturers to compete.
The manufacturers argue that the proposals, which would give independent manufacturers the rights to sell their products throughout the European Union, could jeopardise safety, employment and intellectual property, as well as profits.
The lobbying effort has already delayed a Commission decision from May to June, and then again until September.
The new proposal does not apply to “non-visible” parts, such as engines, or to the original components in cars.