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Home >> GMC >> 1998 >> Forward Control 6.5 F >> Repair and Diagnosis >> External Pages >> Different car >> Section 239 (Engine Controls Self-Diagnostics) >> Diagnostic Tests >> DTC P0401: EGR System - Insufficient Flow >> Conditions For Setting DTC
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Conditions For Setting DTC

WARNING: This page is about a different car, the 2003 Pontiac Aztek and 2003 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.

The MAP changes monitored during the EGR flow test indicate insufficient EGR flow.