Rocker Arm Actuator
Puts a locking pin through a rocker arm to change what a valve does without changing the camshaft. Two systems use the trick: variable valve lift, where the pin selects between a mild and an aggressive cam lobe, and cylinder deactivation, where it unlocks instead so the valve never opens and the cylinder stops breathing. The pin is moved by engine oil pressure admitted by a solenoid — there is no separate fluid — which is why oil level, grade and condition are diagnostic questions on any of its codes rather than maintenance ones. Jammed part-way it can lose contact with its cam lobe and strike it again under valve spring load, which is how these systems damage camshafts and lifters.
Also known as: vtec actuator, afm lifter, dfm lifter, mds solenoid actuator, cylinder deactivation actuator, variable valve lift actuator, switching rocker, collapsible lifter
Referenced by 152 codes
Codes involving this component (152)
- P2647 A Rocker Arm Actuator System Stuck On Bank 1 Stop driving High
- P2652 B Rocker Arm Actuator System Stuck On Bank 1 Stop driving High
- P2657 A Rocker Arm Actuator System Stuck On Bank 2 Stop driving High
- P2662 B Rocker Arm Actuator System Stuck On Bank 2 Stop driving High
- P3401 Cylinder 1 Deactivation/Intake Valve Control Circuit/Open High
- P3402 Cylinder 1 Deactivation/Intake Valve Control Circuit Performance Stop driving High
- P3405 Cylinder 1 Exhaust Valve Control Circuit/Open High
- P3406 Cylinder 1 Exhaust Valve Control Circuit Performance Stop driving High
- P3409 Cylinder 2 Deactivation/Intake Valve Control Circuit/Open High
- P3410 Cylinder 2 Deactivation/Intake Valve Control Circuit Performance Stop driving High
- P3413 Cylinder 2 Exhaust Valve Control Circuit/Open High
- P3414 Cylinder 2 Exhaust Valve Control Circuit Performance Stop driving High
- P3417 Cylinder 3 Deactivation/Intake Valve Control Circuit/Open High
- P3418 Cylinder 3 Deactivation/Intake Valve Control Circuit Performance Stop driving High
- P3421 Cylinder 3 Exhaust Valve Control Circuit/Open High
- P3422 Cylinder 3 Exhaust Valve Control Circuit Performance Stop driving High
- P3425 Cylinder 4 Deactivation/Intake Valve Control Circuit/Open High
- P3426 Cylinder 4 Deactivation/Intake Valve Control Circuit Performance Stop driving High
- P3429 Cylinder 4 Exhaust Valve Control Circuit/Open High
- P3430 Cylinder 4 Exhaust Valve Control Circuit Performance Stop driving High
- P3433 Cylinder 5 Deactivation/Intake Valve Control Circuit/Open High
- P3434 Cylinder 5 Deactivation/Intake Valve Control Circuit Performance Stop driving High
- P3437 Cylinder 5 Exhaust Valve Control Circuit/Open High
- P3438 Cylinder 5 Exhaust Valve Control Circuit Performance Stop driving High
- P3441 Cylinder 6 Deactivation/Intake Valve Control Circuit/Open High
Other components in Valve Timing and Actuation
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