Faulty crankshaft position or engine speed sensor; Damaged, chafed or corroded wiring or connector in the speed sensor circuit; Damaged reluctor ring or trigger wheel, or excessive air gap or debris on the sensor; Faulty camshaft sensor or distributor pickup giving a signal that disagrees with the crank signal (depends on engine); Low battery voltage or poor earth connections upsetting the sensor signal; Incorrect timing belt or chain position, or a worn drive affecting signal correlation; Fault within the engine control unit or ignition module.

P0320

Ignition/Distributor Engine Speed Input Circuit.

Generic
Powertrain
Generic code
High severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
3: AreaIgnition system or misfire
20: FaultThe specific fault in that area

What it means

P0320 is the generic code for a fault in the ignition or distributor engine speed input circuit. The engine control unit has seen a missing, erratic or implausible engine speed signal from the crankshaft or distributor-based speed sensing circuit, or the signal does not agree with other inputs such as the camshaft sensor. How the circuit is arranged, and which sensor feeds it, depends on the model and engine.

Symptoms

Engine cranks but is hard to start or will not start
Engine stalls unexpectedly or cuts out while driving
Rough running, misfiring or hesitation
Rev counter flickers, drops to zero or does not work
Loss of power or poor acceleration
Check engine light on

Possible causes

Faulty crankshaft position or engine speed sensorlikely
Damaged, chafed or corroded wiring or connector in the speed sensor circuitlikely
Damaged reluctor ring or trigger wheel, or excessive air gap or debris on the sensorpossible
Faulty camshaft sensor or distributor pickup giving a signal that disagrees with the crank signal (depends on engine)possible
Low battery voltage or poor earth connections upsetting the sensor signalpossible
Incorrect timing belt or chain position, or a worn drive affecting signal correlationrare
Fault within the engine control unit or ignition modulerare

How to diagnose

Read all stored and pending codes and review the freeze frame data, noting engine speed, load and temperature when the fault set
Check for related codes such as camshaft sensor, misfire or ignition faults that point to a common cause
Check battery condition and charging voltage, and inspect the main earth connections
Visually inspect the sensor, wiring and connectors for chafing, heat damage, oil contamination, corrosion or loose pins
Compare live engine speed readings on the scan tool against the rev counter while cranking and running
Check the sensor mounting, air gap and condition of the reluctor ring or trigger wheel for damage or debris
Test the sensor resistance or signal output with a multimeter or oscilloscope against the manufacturer specification for that engine
Where the signal correlation is suspect, verify mechanical timing against the manufacturer procedure

How to fix

Replace the faulty crankshaft or engine speed sensor
Repair or replace damaged wiring and clean or renew corroded connectors
Clean, refit or correct the sensor mounting and replace a damaged reluctor ring or trigger wheel
Replace a faulty camshaft sensor or distributor pickup if it is the cause
Restore battery health and repair poor earth connections
Correct the engine timing if it is found to be out, following the manufacturer procedure

Can I keep driving?

High severity

Avoid driving the car if it is stalling, cutting out or running badly, as losing power unexpectedly is a safety risk and misfires can damage the catalytic converter. Have it diagnosed promptly.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.