DTC P0401 Or DTC P0402: Condition

DTC P0401 is set when difference in intake manifold absolute pressure value when EGR valve is opened and when EGR valve is closed is less than specified value.

DTC is set when difference in intake manifold absolute pressure value when EGR valve is opened and when EGR valve is closed is more than specified value. MIL is illuminated when Engine Control Module (ECM) detects malfunction during 2 consecutive drive cycles. Possible causes are:

• EGR valve malfunction.
• EGR passage restricted.
• Manifold Differential Pressure (MDP) sensor malfunction.
• ECM malfunction.