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Home >> Toyota >> 2004 >> Matrix Base, FWD, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 136 (Engine Control System Self Diagnostics - 4-Cylinder) >> Diagnostic Tests >> DTC P0401: Insufficient Exhaust Gas RECIRCULATION Flow Detected >> Possible Causes
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Possible Causes

WARNING: This page is about a different car, the 2003 Toyota Tacoma. However, it is still accessible from the selected car via links, so may be relevant.

This DTC uses two-trip detection logic. DTC is set when there is a small difference in the temperature between EGR gas temperature sensor and the ambient air temperature with engine at normal operating temperature and vehicle is driven at 50 MPH for 3-5 minutes. Possible causes are: