Cylinder Deactivation Lifter Stuck Activated
2012-2015 BMW 320i 2.0L I4 Turbo N20
Description
A cylinder deactivation lifter is mechanically stuck in the deactivated (collapsed) position. The affected cylinder is not firing.
Symptoms
- Check Engine Light
- Engine misfire
- Rough idle and vibration
- Reduced power
- Exhaust smell of unburned fuel
- Catalytic converter damage risk
Common Causes
- Collapsed lifter mechanism
- Oil sludge jamming lifter
- Lifter roller bearing failure
- Oil pressure loss to lifter
- Excessive wear on lifter body
Diagnostic Steps
- Identify which cylinder is deactivated permanently
- Check oil pressure at affected lifter
- Perform compression test on that cylinder
- Check for oil sludge
- Inspect lifter via valve cover removal if accessible
Repair Notes
Replace collapsed deactivation lifter. This requires camshaft and lifter removal. Inspect cam lobe for damage. Full engine oil flush recommended.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P3623 on Other Vehicles
Common Questions
What does code P3623 mean on a 2012-2015 BMW 320i?
P3623 stands for "Cylinder Deactivation Lifter Stuck Activated". A cylinder deactivation lifter is mechanically stuck in the deactivated (collapsed) position. The affected cylinder is not firing.
What are the symptoms of P3623 on a BMW 320i?
Common symptoms of P3623 include: Check Engine Light, Engine misfire, Rough idle and vibration, Reduced power, Exhaust smell of unburned fuel, Catalytic converter damage risk.
What causes P3623 on a 2012-2015 BMW 320i?
Common causes of P3623 include: Collapsed lifter mechanism, Oil sludge jamming lifter, Lifter roller bearing failure, Oil pressure loss to lifter, Excessive wear on lifter body.