Abstract: In this paper, the technical conversion of electronic control gasoline injection engine into LPG liquid injection (LPI) engine is introduced and the research about LPI engine performance is conducted. The results show that LPI engine power can get the same level with original gasoline engine, fuel consumption has some improvement, and exhaust emission can meet the Europe II standard. However, according to the durability test, the materials of the intake valves and intake valve seats are to be improved.

Key words: LPG engine, liquid injection system, alternative fuel