Powertrain, generic (extended)

P26EF Engine Sound Control B Circuit Performance

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P26EF is the functional fault of the second sound actuator: wiring checks pass, yet flap or valve B does not reach or report the commanded state in time. No maker documents P26EF publicly. The A-side equivalent P26DE is well described for the Nissan GT-R, where the electric valve on the main muffler was the cause and could be renewed separately after a software check, and Ford monitors its exhaust valves for a stuck flap via the PWM feedback of a smart driver. Those cases suggest the same suspects for B: binding from soot or rust, a seized shaft after long periods in one position, or a worn actuator gearbox. Unlike P26EC to P26EE, measuring voltages rarely finds the fault; a visual and movement check of the flap does.

Likely causes

Flap B binding due to soot, rust or a seized shaft
Worn gearbox or weak motor in actuator B
Evaluation in the module software too sensitive

Symptoms

  • Check engine light
  • Sound of the second branch changes late or not at all
  • Rattle from the flap housing

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€50–1,200
Time0.5–3 h

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

Parts involved

sound actuatorexhaust sound valve

Related codes

P26ECP26EDP26EEP26DEP2BFB

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