P0320 OBD-II Trouble Code: Ignition/Distributor Engine Speed Input Circuit Malfunction

Check Engine Light

P0320 code definition

Ignition/Distributor Engine Speed Input Circuit Malfunction

What the P0320 code means

When the P0320 diagnostic trouble code is stored by the Engine Control Module (ECM), it is an indication that there is a malfunction in the ignition/distributor engine speed input circuit

A quick background into this system:

The purpose of the ignition/distributor engine speed sensor is to provide information to the ECM regarding the rotational speed and position of the crankshaft.

With this information, the ECM is able to regulate the timing of ignition spark and the distribution of fuel. If the ignition/distributor engine speed sensor is not working properly, the ECM is not able to receive the signal from the ignition/distributor engine speed sensor.

As a result, the ECM will be unable to regulate the ignition spark timing and fuel distribution, which will cause a disruption in the operation of the vehicle.

Related diagnostic trouble codes:

  • P0321 OBD-II Trouble Code: Ignition/Distributor Engine Speed Input Circuit Range/ Performance

  • P0322 OBD-II Trouble Code: Ignition/Distributor Engine Speed Input Circuit No Signal

  • P0323 OBD-II Trouble Code: Ignition/Distributor Engine Speed Input Circuit Intermittent

What causes the P0320 code?

  • Engine running rough
  • Misfiring condition
  • Low battery charge
  • Bad crankshaft position sensor
  • Crankshaft position sensor wiring and/or connector that is defective or corroded
  • Bad camshaft position sensor
  • Camshaft position sensor wiring and/or connector that is defective or corroded
  • Bad ignition/distributor engine speed sensor
  • Ignition/distributor engine speed sensor wiring or connector that is shorted or corroded
  • Poor electrical connection in the ignition/distributor engine speed sensor circuit
  • Bad ECM

What are the symptoms of the P0320 code?

  • Check Engine Light is on
  • Vehicle is hard to start or will not start at all
  • Vehicle may stall out
  • Vehicle may die and be unable to restart
  • Vehicle may have a loss of power

It is common for there to be no symptoms at all.

How does a mechanic diagnose the P0320 code?

  • Uses an OBD-II scanner to get the trouble codes that have been stored by the ECM

  • Views OBD-II scanner data to see if the ignition/distributor engine speed sensor, the crankshaft sensor, and the camshaft sensor are operating with the proper voltage

  • Visually inspects ignition/distributor sensor wiring and connectors for damage and/or corrosion

  • Visually inspects crankshaft sensor wiring and connectors for damage and/or corrosion

  • Visually inspects camshaft sensor wiring and connectors for damage and/or corrosion

  • Repairs wires and/or connectors as necessary

  • Repairs misfiring condition if a misfire code has been stored by the ECM

  • Completes a test drive of the vehicle to see if the code comes back

If theses diagnostic steps do not resolve the P0320 code, it is possible that the ECM needs to be replaced or reprogrammed. In this case, it will be necessary to follow the manufacturer’s diagnostic procedure.

Common mistakes when diagnosing the P0320 code

Quite often, the mistake that is made when diagnosing the P0320 code is replacing the wrong sensor. Sometimes, the crankshaft sensor is replaced when the problem is really the ignition/distributor engine speed sensor.

Other times, the crankshaft is replaced when the problem is really the camshaft sensor. Since these sensors work closely together to achieve the same thing, it is important to make sure the right component is being replaced.

It is also important to keep in mind that misfire codes may be stored in addition to the P0320 diagnostic trouble code, and misfire conditions need to be diagnosed and repaired in order to successfully resolve the problem. Another common mistake is neglecting to inspect the ignition/distributor engine speed sensor wiring and connector.

How serious is the P0320 code?

The P0320 diagnostic trouble code is considered moderately serious. If the code is present and the Check Engine Light is on, but there are no other symptoms, the driver may not experience any driveability issues that would render the vehicle unreliable.

However, allowing an extended period of time pass without addressing this problem will allow the condition to worsen in addition to possibly damaging other engine components.

What repairs can fix the P0320 code?

Additional comments for consideration regarding the P0320 code

Before replacing the ignition/distributor engine speed sensor, be sure to rule out the possibility that the crankshaft position sensor or camshaft position sensor is defective. Also, remember to diagnose and repair any misfire diagnostic trouble codes that have been stored by the ECM.

Need help with a P0320 code?

YourMechanic offers certified mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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