LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Scion >> 2008 >> tC Base, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> Remove, Overhaul & Install >> 2AZ-FE Engine Control System >> SFI System >> DTC P0171: System Too Lean (Bank 1); DTC P0172 System Too Rich (Bank 1) >> Typical Malfunction Thresholds
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Typical Malfunction Thresholds

TYPICAL MALFUNCTION THRESHOLDS

Purge-cut Executing
Either of the following conditions is met: -
Average between short-term fuel trim and long-term fuel trim 38% or more (varies with ECT)
Average between short-term fuel trim and long-term fuel trim -32% or less (varies with ECT)