Trouble codes › P0340

P0340 Camshaft Position Sensor "A" Circuit (Bank 1 or Single Sensor)

Engine timing

P0340 means the engine computer isn't getting a usable camshaft position sensor signal, which can cause hard starting.

The camshaft position sensor tells the engine computer where the camshaft is, so it knows which cylinder is on its power stroke. P0340 means the computer isn't getting a usable signal from that sensor on bank 1 (or the single sensor, on engines with one).

Can I keep driving? Yes, but get it fixed soon.

Many engines still run, using the crank sensor alone, but may be hard to start or run poorly. Drive only if it runs normally, and get it fixed soon.

Common causes

  1. A failed camshaft position sensor
  2. Damaged wiring or a corroded connector
  3. Low battery voltage or a weak starter making the signal too slow while cranking
  4. A timing chain or belt problem, or a damaged cam reluctor (less common)

Symptoms

  • Longer cranking before it starts, or no start
  • Rough running, stalling or hesitation
  • Check-engine light

Common on: Nissan Altima, Nissan Rogue, Nissan Sentra

Known problems: Ford 5.4L 3-valve cam phasers and timing · Nissan 2.5L crankshaft and camshaft sensor stalling

What to check first

  1. Check the battery and that the engine cranks at normal speed.
  2. Inspect the cam sensor's connector and wiring, especially for oil in the connector.
  3. With a scan tool, check for the cam signal while cranking if your tool shows it.
  4. Test the sensor's power, ground and signal as your service information describes before replacing it.

What does P0340 mean on your vehicle?

The likely cause depends on your engine. iRepair researches your exact year, make, model and engine (service bulletins, recalls and owner reports) and tells you what to check first. Your first 3 questions are free.

Ask iRepair about P0340

No scanner? Most auto parts stores read check-engine codes for free.

Related codes

General guidance for P0340 on most vehicles. Some makers use the same code a little differently; confirm in the service information for your vehicle, put safety first, and see a professional when in doubt.