Powertrain
Definition only
Lights the check engine lamp
P2651: B Rocker Arm Actuator System Performance/Stuck Off Bank 1
Standardized SAE J2012 code · P26xx — Computer and output circuits
What does P2651 mean?
The rocker arm actuator B on bank 1 is commanded to engage but does not switch. Engine stays in the wrong lift or cylinder mode under load.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Common causes
- High Low oil pressure cannot move the actuator
- Medium Mechanical lock pin stuck in unactivated position
- Low Carbon or debris buildup preventing free movement
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of P2651 on the same make and model first.
P2651 in the community
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