Vietnam's science and technology ministry was on Wednesday asked to report to the prime minister the result of tests of fuel quality following many instances of vehicles catching fire or exploding last year.
Substandard fuel is one of the suspects in the recent spate of motorbike and car fires and explosions, Deputy PM Hoang Trung Hai said in a note sent to the ministry.
According to statistics from the Hanoi Firefighting Department, there were 42 vehicle explosions in the city between December 1, 2010 and December 18, 2011.
The explosions happened to cars and motorbikes of various makes including Hyundai, Daewoo, BMW, Mercedes, Ford, Mazda, Mitsubishi, Kia, Toyota, SYM and Honda.
Local media reported a total of 89 vehicle explosions 50 cars and 39 motorbikes that killed two and injured two others across the country last year.
On January 3, the Ministry of Science and Technology's Product Quality Management Department announced it had found six samples of substandard petroleum in Hanoi and Ho Chi Minh City.
It said two samples had higher-than-allowed methanol content and four samples did not have the required octane rating (or octane number) a standard measure of the performance of a motor or aviation fuel.
The higher the octane number, the more compression the fuel can withstand before detonating.
According to the department, most vehicles in Vietnam use gasoline with high octane rating, like A92 and A95.
It says those who use poor quality gasoline or gasoline of unclear origin can face engine failures, low fuel economy, and the risk of fire and explosions.