Cylinder 9 Pressure Sensor Circuit Intermittent or Erratic
Cylinder 9 pressure sensor signal jumps or drops out intermittently — connector or wiring issue. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
Affected components
- Cylinder pressure sensor 9
- Cylinder pressure wiring 9
Common causes
- High likelihood: Intermittent contact at connector or terminal
- Medium likelihood: Harness chafed - intermittent short
- Low likelihood: Connector with intermittent contact under vibration
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
Related codes
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.