Powertrain, generic (extended)

P264E "A" Rocker Arm Actuator Position Sensor Circuit Intermittent/Erratic (Bank 1)

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P264E covers a feedback signal from the position sensor of actuator A, bank 1, that drops out or jumps for short moments rather than staying low or high. Loose terminals, a cracked wire flexing with engine movement, or interference on an unshielded line are the usual reasons, and the fault may vanish when the vehicle is parked. CARB requires lift system inputs to be monitored for such rationality and continuity problems. No manufacturer documents P264E publicly. Because the lift controller depends on a steady reading, jumps can make it hunt or fall back to a fixed lift, which drivers notice as surging or uneven idle. Wiggle tests on the harness help locate it.

Likely causes

Loose or spread terminal in the sensor connector
Wire cracked inside the insulation by engine movement
Electrical interference on the signal line

Symptoms

  • MIL on, sometimes clearing by itself
  • Surging or hesitation
  • Uneven idle

Repair estimate

DifficultyHardWorkshop job
Parts and labour€60–600
Time0.5–3 h

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

Parts involved

rocker arm position sensor a b1wiring harness

Related codes

P264AP264BP266EP265E

References: law.cornell.edu, en.wikipedia.org.