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Malfunction Threshold

The ratio of the current EGR flow to the normal EGR flow is 20 % or less for at least 3.5 seconds.

The ratio is derived from the actual and estimated MAP values before and after the EGR valve was opened. The estimated MAP difference value is shown in the table.

Engine speed Barometric pressure
52 kPa (15.4 inHg, 390 mmHg) 102 kPa (30.0 inHg, 760 mmHg)
1,000 rpm 18 kPa (5.2 inHg, 132 mmHg) 42 kPa (12.3 inHg, 313 mmHg)
2,500 rpm 8 kPa (2.3 inHg, 58 mmHg) 18 kPa (5.4 inHg, 138 mmHg)