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Home >> Lexus >> 2012 >> IS 250 Base, AWD >> Repair and Diagnosis >> Engine Performance >> Testing & Diagnosis >> Engine Control System (Diagnostic Codes (P0010-P0175)) >> SFI System >> DTC P0171: System Too Lean (Bank 1); DTC P0172: System Too Rich (Bank 1); DTC P0174: System Too Lean (Bank 2); DTC P0175: System Too Rich (Bank 2) >> Typical Malfunction Thresholds
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Typical Malfunction Thresholds

EVAP purge-cut Executing
Either of the following conditions is met: Condition 1 or 2
1. Average between short-term fuel trim and long-term fuel trim 35% or more (varies with engine coolant temperature)
2. Average between short-term fuel trim and long-term fuel trim -35% or less (varies with engine coolant temperature)