What does code P349B mean?

Q: What does code P349B mean?

Cylinder 4 Deactivation/Intake Valve Performance. P349B indicates that the powertrain control module has detected a performance fault in the cylinder 4 deactivation system or its associated intake valve control, meaning the engine cannot properly switch cylinder 4 between full operation and deactivated mode. The computer monitors valve lift and timing via sensors and compares actual response to commanded action, setting this code when the expected change does not occur within a calibrated window.

DTC codes / P34xx · Auxiliary emission controls / P349B

P349BCylinder 4 Deactivation/Intake Valve Performance

P349B indicates that the powertrain control module has detected a performance fault in the cylinder 4 deactivation system or its associated intake valve control, meaning the engine cannot properly switch cylinder 4 between full operation and deactivated mode. The computer monitors valve lift and timing via sensors and compares actual response to commanded action, setting this code when the expected change does not occur within a calibrated window.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyProfessional

AreaAuxiliary emission controls

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.