Engine

P03F7 — B Camshaft Actuator Position Sensor C Range/Performance, Bank 1

Severity: medium Drive with care, to a shop

What P03F7 means

The engine control module compares the commanded position of the bank 1 B camshaft with the signal from actuator position sensor C and finds it out of range or not matching. Variable valve timing uses an oil control valve and a cam phaser to shift the camshaft, and the sensor reports the result. Without reliable feedback, the module cannot control cam timing accurately.

Symptoms

  • Check engine light on
  • Rough idle
  • Worse fuel economy
  • Reduced engine power
  • Stalling in some conditions
  • Possible misfires

Possible causes

  1. Faulty camshaft actuator position sensor
  2. Damaged wiring or poor connector contact at the sensor
  3. Low oil level, degraded oil or low oil pressure
  4. Faulty VVT solenoid (oil control valve)
  5. Faulty camshaft phaser/adjuster
  6. Stretched timing chain or incorrect timing
  7. PCM fault (rare)

How to diagnose

  1. Scan all codes and freeze frame data, and note any other VVT or camshaft codes
  2. Check oil level and condition; change oil and filter if dirty or overdue
  3. Inspect the sensor, harness and connector for chafing, corrosion, kinks and oil
  4. Test sensor power, ground and signal with a multimeter or scope
  5. Compare specified and actual cam angle in live data
  6. Command the VVT solenoid with a scan tool, check response, and measure its resistance and screen
  7. Verify oil pressure and phaser condition
  8. If deviation persists, check timing marks and timing chain stretch

Common fixes

  • Replace the camshaft actuator position sensor
  • Repair wiring or replace the connector
  • Change oil and filter, clean or replace the VVT oil control valve
  • Replace the camshaft phaser
  • Replace the timing chain and tensioners and set timing to the marks

Questions and answers

What does P03F7 mean?

The PCM found that the signal from the B camshaft actuator position sensor C on bank 1 does not match what is expected. It relates to feedback in the variable valve timing system.

Can I drive with P03F7?

Only briefly and carefully until it is diagnosed. If the cause is oil or the timing chain, continued driving can damage the engine.

Where should I start diagnosing P03F7?

Start with oil level and condition, then inspect the sensor wiring and connector. After that, compare specified and actual cam timing in live data.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.