A BMW vehicle not subject to the carmaker’s nationwide recall caught fire Wednesday, deepening the mystery of the cause of a series of incidents that have fueled safety concerns here.

A BMW X1 vehicle burst into flames while traveling near a village in Imsil country of North Jeolla Province at 4:17 a.m., according to police and firefighters. No injury was reported.

The vehicle, manufactured in 2012, is the 40th BMW vehicle to have caught fire this year. However, the compact SUV powered by a diesel engine is not on BMW’s recall list. 

The incident came a day after the South Korean government banned the operations of uninspected BMW vehicles subject to a recall. The Ministry of Transport requested head of municipalities to issue administrative orders to stop operating BMW recalled models if not for the purpose of inspection.

The recalled models are all diesel vehicles. The list of 42 models includes the 120d, 320d, 420d, 520d, 535d and 730d, all manufactured before September 2016.

As fires involving BMW vehicles have continued, questions have been raised over the effectiveness of the government’s action, as owners of other BMW vehicles remain concerned.

Of the 40 incidents of fire, 11 involved vehicles not on the recall list. Gasoline-powered vehicles also caught fire, including the M3 Convertible, 528i and 740i.

The Transport Ministry said it would inspect other BMW vehicles and vehicles by other carmakers, to establish the cause. The cause of the BMW fires, however, remain ambiguous.

BMW has said an exhaust gas recirculation module, a part needed for the diesel exhaust system, is at the center of the problem, and safety concerns would be eased by replacing the part via its recall that started Wednesday.

However, local experts have suggested that the faulty EGR is only part of the problem and there could be other issues.

Park Byoung-il, a master technician, pointed out the German carmaker’s use of the plastic EGR valve, saying that it is not enough to resist exhaust gas that usually goes up to 1,000 degrees Celsius.

“The company also admitted that there was a coolant leakage, which means that the EGR cooler didn’t really work at all to bring the temperature down from 800-1,000 degrees Celsius. The plastic valve is not able to withstand exhaust gas that is more than 150 degrees Celsius,” he said.

Meanwhile, citing safety concerns, the Ministry of Home Affairs has also banned the parking of BMW recalled models underground at 10 government complexes in Seoul, Daejeon, Gwacheon and Sejong. Some commercial buildings have been posting signs that say they will not accept BMW vehicles for underground parking.

By Cho Chung-un (christory@heraldcorp.com)