Fault Diagnosis of Car Engine by Using a Novel GA-Based Extension Recognition Method

Table 2

Fault types relative to the multiple frequency of the engine rotational speed.

Items	Fault types	Characteristic frequency 9.5th~12th multiple frequencies
1	No fault	Nothing
2	Spark plug is too large to 2.0 mm	Nothing
3	Spark plug is too small to 0.2 mm	12
4	No fuel injection in the 1st cylinder	9.5, 10.5, 12
5	No fuel injection in the 2nd cylinder	9.5, 12
6	No fuel injection in the 3rd cylinder	9.5, 10.5, 12
7	No fuel injection in the 4th cylinder	9.5, 12
8	No fuel injection in the 5th cylinder	9.5, 10.5, 12
9	No fuel injection in the 6th cylinder	9.5, 12
10	No ignition in the 6th cylinder	9.5, 10.5, 12
11	No ignition in the 5th cylinder	9.5, 12
12	No ignition in the 4th cylinder	9.5, 10.5, 12
13	No ignition in the 3rd cylinder	9.5, 12
14	No ignition in the 2nd cylinder	9.5, 10.5, 12
15	No ignition in the 1st cylinder	9.5, 12
16	Oxygen sensor malfunction	12