South Korea's government on Sunday ordered GM Korea Co. to recall 15,056 Chevrolet Orlando compact multi-purpose vehicles for emission-related problems.

The order affects Orlandos using the 2.0 liter engine that uses liquefied petroleum gas as fuel, the environment ministry said.

The vehicles made from May 6, 2011 to Oct. 7, 2013 have been found to emit carbon monoxide beyond permissible levels.

The colorless and odorless gas can be toxic to people above a certain concentration in the atmosphere and is tightly regulated by environmental and health authorities.

The ministry said it found defects after testing 10 Orlandos from November to March. All vehicles checked emitted more than 1.847 grams per kilometer of CO gas. This is noticeably higher than the 1.06g/km limit set by Seoul.

In addition, tests showed the nonmethane organic gas released by the MPVs exceeded the 0.025g/km limit. NMOG refers to the sum of all organic air pollutants, excluding methane gas.

The carmaker will replace emission control software free of charge starting on Monday at its service stations nationwide. For cars that have been driven for more than 80,000 kilometers, the company will clean the throttle body valve to get rid of carbon buildup.

GM Korea, which makes cars in South Korea under the Chevrolet brand, said the buildup of carbon within the throttle body is the reason for the problem. This defect triggers incomplete combustion that causes the excessive release of CO and NMOG. (Yonhap)