Powertrain, generic · Ignition system or misfire

P03E8 A Camshaft Position Actuator Position Sensor C Circuit High Bank 1

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

On some engines the intake cam phaser (camshaft position actuator A) has its own position sensors, which tell the engine module where the phaser actually is; sensor C is the third of them, bank 1 the side with cylinder 1. P03E8 means the sensor signal stays above its upper limit – typically an open sensor ground, a signal wire shorted to 5 V or battery voltage, or a faulty sensor. No manufacturer document available to us uses this code. GM's 2.7-litre engine monitors comparable position sensors on its sliding camshaft under other codes (P2C05 ff), with an open circuit above 200 kΩ and a short below 0.5 Ω in 4 of 5 samples – only as a comparison. The phaser is then usually held in its base position, with a loss of power.

Likely causes

Sensor ground open or connector corroded
Signal wire shorted to 5 V or vehicle voltage
Sensor faulty
Engine module

Symptoms

  • Check engine light on
  • Cam phasing held in its base position, loss of power
  • Possibly rough idle or higher consumption

Repair estimate

DifficultyMediumDIY possible
Parts and labour€60–400
Time0.5–2.5 h

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

Parts involved

cam phaser position sensor ccam phaser intake bank1sensor wiringengine control module

Related codes

P03E5P03E6P03E7P03F9P2B42P0643

References: law.cornell.edu, gsi.ext.gm.com.