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P0172 - System Too Rich (Bank 1)

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P0172 - SYSTEM TOO RICH (BANK 1)

Description:  The adaptive fuel strategy continuously monitors the fuel delivery hardware. The test fails when the adaptive fuel tables reach a lean calibrated limit. Refer toPOWERTRAIN CONTROL SOFTWARE Fuel Trim for more information.
Possible Causes:  Fuel System:
  • Damaged or leaking fuel pulse damper
  • Leaking fuel injectors
  • Fuel return line restricted
  • Fuel rail pressure sensor bias
  • EVAP canister purge valve is leaking when the canister is full

Base engine.
  • Engine oil contamination

Intake Air System:
  • Damaged or contaminated mass air flow (MAF) sensor
Diagnostic Aids:  View the Freeze Frame Data to determine the operating conditions when the DTC was set. Observe the LONGFT1 and LONGFT2 PIDs. Refer toADAPTIVE FUEL DTC DIAGNOSTIC TECHNIQUES for more information and the appropriate pinpoint test for specific concern identification.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All   - - refer to PINPOINT TEST H .
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