Driver's license written test question bank, effective 2026-03-09

40. Which of the following is NOT a problem that can occur in cars when refueling with fake petroleum products?

  1. ①Increased engine noise due to corrosion and damage of the fuel supply device
  2. ②Reduced power and fuel efficiency due to damage to the injector that injects fuel
  3. ③Reduced power due to reduction of engine friction caused by increased lubricity
  4. ④Power-downs due to damage to the high-pressure fuel pump supplying fuel
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Answer ③

The English PDF has no explanation for this question. The Korean page carries the official explanation. Korean version of this question

Source KoROAD Safe Driving Integrated Civil Service, Driver's License Written Test Question Bank [English] (effective 2026-03-09), post 1923, Download the source PDF source PDF page 12 (checked on 2026-09-04). The question and answer are the KoROAD text as published. The buttons and notes on this page were written by the developer and have not yet been checked by a native speaker. The questions and answers themselves are the official KoROAD text.