DTC Decoded: P1345

crankshaft

Diagnostic code: P1345

Make: Chevrolet

Decode: Position of Crankshaft or Position Correlation of the Camshaft

Code detection: The ECM has determined that the sensor positions to the camshaft or the crankshaft are out of time.

Symptoms of this code:

  • The engine is hard to start.
  • The engine stalls while driving.
  • The service engine light comes on.

What causes this code?

  • Faulty sensor that detects camshaft position
  • Faulty sensor that detects crankshaft position
  • Valve timing off, which makes this an engine mechanical condition
  • Mounting loose for the sensor to either the camshaft or crankshaft

What the techs say:

If this code came on after internal repairs on the engine, then you should check the engine to ensure you have the proper mechanical timing.

  • Take the camshaft cover off.
  • Set the number one cylinder at top dead center by making sure the alignment marks on the cylinder and the marks on the intake cam sprockets and exhaust are lined up.

If codes P1345 or P0016 are resetting, but are not linked to any engine performance issues and these causes are not related to the issue, you may need to replace the sprocket to the Cam Phaser Actuator.

Chevrolet Code Description:

P1345

The sensor that determines the crankshaft position (CKP) is known as a variable reluctance sensor, which is a permanent magnet generator. The sensor has a magnetic field that the crankshaft mounted reluctor wheel alters. The reluctor wheel has seven slots that have been machined in. Of those seven, six are spaced an equal 60 degrees apart, and the seventh is 10 degrees from one of the other slots. There are seven pulses produced by the CKP for each crankshaft revolution. The pulse that comes from the 10-degree slot is the synch pulse that is used to synchronize the coil firing sequence in relationship to the position of the crankshaft. The powertrain control module (PCM) is connected to the CKP sensor by a low reference circuit and a signal circuit.

The notched reluctor wheel that is built into the exhaust camshaft sprocket triggers the camshaft position sensor (CMP). The sensor for the CMP delivers six signal pulses for every revolution of the camshaft. The notches on the wheel are all different sizes that represent each cylinder for easy identification. The CMP and CKP are pulse width encoded for continual monitoring by the PCM to determine their relationship. By monitoring the relationship, the position of the camshaft actuator’s phasing is controlled at the correct value. The signal is also used by the PCM to identify each cylinder’s compression stroke. It also is used for sequential fuel injection. A 12-volt, signal and low reference circuit connect the PCM and the CMP sensor.