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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 P0402: Excessive Exhaust Gas RECIRCULATION Flow Detected >> Circuit Description
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Circuit Description

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.

Exhaust Gas Recirculation (EGR) system recirculates exhaust gases to reduce combustion temperatures and exhaust emissions. The amount of exhaust gases that EGR valve recirculates is controlled by EGR vacuum modulator according to engine load. EGR system is turned off if engine is not at normal operating temperature, during deceleration, during light load or when engine is racing.