Powertrain, generic (extended)

P2BF1 Fuel Control System B Too Rich Bank 1

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

With P2BF1 the PCM has seen bank 1 too rich while fuel came through the port injectors, Ford's fuel system B. Ford flags it when the long-term value sits beyond minus 25 percent and the short-term value still takes away above 1 percent, for a 2 second window in closed loop. Since this monitor only runs with the canister purge valve closed, vapour from the evaporative system cannot explain the result; the excess fuel comes from the injection side or from a wrong air reading. Typical findings are a port injector that leaks into the intake runner, too much low-side fuel pressure or a mass air flow signal that reads low. If the rich condition is present in DI mode too, Ford stores P0172 instead. Ford names P2BF1 in its F-150 reflash bulletins for the 2.7 L and 5.0 L engines.

Likely causes

Port injector on bank 1 leaking or dribbling
PCM software, Ford reprogramming bulletins
Low-side fuel pressure above specification
Mass air flow sensor under-reporting

Symptoms

  • Check engine light on
  • Fuel smell, black exhaust deposits
  • Rough idle when warm

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€80–1,200
Time0.3–4 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

fuel injectorsfuel pressure regulatorintake system

Related codes

P2BF0P2BF3P2BEDP0172P2188

References: fordservicecontent.com, static.nhtsa.gov, static.nhtsa.gov, law.cornell.edu.