Table 1: Typical car engine symptoms.
Case no. Symptoms
x1 Difficult-to-start
x2 Stallon occasion
x3 Backfire during acceleration
x4 Unstable idle speed or misfire
x5 Sluggish acceleration
x6 Knocking
x7 Backfire in exhaust pipe
x8 Abnormal inlet pressure
x9 Abnormal throttle sensor signal
x10 Abnormal coolant temperature
x11 Abnormal lambda signal