P0323: Ignition/Distributor Engine Speed Input Circuit Intermittent
The P0323 code indicates that the Engine Control Module (ECM) has detected an intermittent or erratic signal from the ignition/distributor engine speed input circuit. This circuit typically involves the crankshaft position sensor or distributor pickup coil, which provides engine RPM data to the ECM. An intermittent signal can cause misfires, stalling, or poor performance. Common causes include a faulty sensor, damaged wiring, loose connections, or a failing distributor.
1. Most Common Causes
- Faulty crankshaft position (CKP) or camshaft position (CMP) sensor
- Damaged, corroded, or loose wiring or connectors in the engine speed sensor circuit
- Electromagnetic interference (RFI/EMI) in the sensor circuit due to poor shielding
- Damaged, dirty, or broken teeth on the reluctor ring (tone wheel)
- Internal PCM failure (rare)
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine misfire or rough idle
- Intermittent stalling or hesitation during acceleration
- Difficulty starting the engine
3. Step-by-Step Diagnosis
Step 1: Scan the vehicle for additional codes and record freeze frame data.
Step 2: Visually inspect the crankshaft position sensor and distributor wiring for damage, corrosion, or loose connections.
Step 3: Use a multimeter to test the sensor's resistance and AC voltage output while cranking the engine.
Step 4: Check for intermittent signal by wiggling the wiring harness while monitoring the sensor signal with a scan tool or oscilloscope.
Step 5: If no issues found, replace the crankshaft position sensor or distributor pickup coil as needed.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive with this code as the intermittent signal can cause sudden stalling or loss of power, leading to unsafe driving conditions.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for parts and labor, depending on the specific sensor and vehicle model.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.