P0322 – Meaning, Symptoms, Causes & How to Fix It

P0322 – Ignition/Distributor Engine Speed Input Circuit No Signal means the engine control unit is not receiving any RPM signal from the ignition system or distributor. This signal normally comes from the crankshaft position sensor (CKP), camshaft position sensor (CMP), or a distributor pickup. Without it, the ECU cannot control spark timing or fuel delivery, often resulting in a no-start or stalling condition. This guide explains what P0322 means, its symptoms, causes, diagnosis steps, and the best repair options.

What Does P0322 Mean?

P0322 is a generic OBD-II code indicating that the ECU is detecting zero RPM input when there should be a valid signal. These signals are essential for engine synchronization. If the ECU does not see engine rotation, it immediately disables the ignition coils and fuel injectors as a safety measure.

This code is common on vehicles with failing CKP sensors, damaged wiring, or worn distributor components, and is often linked to sudden stalling or complete no-start issues.

Quick Reference

OBD-II Family: P-Code (Powertrain)
Scope: Generic
System: Ignition / Engine Speed Sensing
Difficulty Level: Moderate–Advanced
Estimated Repair Cost: €70–€350+
Last Updated: 9 December 2025

Real-World Example / Field Notes

A compact car was towed in after stalling on the highway. The tachometer dropped to zero instantly and the engine died. Live data confirmed no RPM signal during cranking. The crankshaft position sensor had failed internally due to heat soak. Installing a new CKP sensor restored spark and fuel, and the engine started immediately.

Another case involved a pickup with random stalling. The distributor pickup coil had an intermittent open circuit that caused the RPM signal to drop out. Replacing the distributor pickup eliminated the issue permanently.

Symptoms of P0322 – Ignition/Distributor Engine Speed Input Circuit No Signal

No-start condition: The engine cranks but will not fire.
Sudden stalling: Loss of RPM signal instantly shuts off spark and fuel.
Zero RPM on scanner: No crank signal detected during engine rotation.
Tachometer dead: RPM needle stays at zero during cranking.
Misfires before failure: The signal may weaken before it fully fails.
Check engine light: Often appears immediately after stalling or failed start.

Common Causes of P0322

Most Common Causes

Failed crankshaft position sensor (CKP)
Failed camshaft position sensor (CMP)
Distributor pickup coil failure (if equipped)
Broken, shorted, or corroded CKP/CMP wiring
Bad sensor connector or loose terminal fit

Less Common Causes

Damaged reluctor ring or tone wheel
Faulty ignition control module (ICM)
Internal ECU failure
Aftermarket alarm or remote-start wiring interference
Incorrect air gap between sensor and tone wheel

Diagnosis: Step-By-Step Guide

P0322 diagnosis focuses on finding why the ECU receives zero RPM signal — usually due to a failed sensor or circuit fault.

Tools You’ll Need

OBD-II scan tool with live data, multimeter, oscilloscope (ideal), wiring diagram, test light, and basic hand tools.

Verify no RPM signal: Watch RPM on live data during cranking — it should rise quickly.
Inspect CKP/CMP sensors: Check for physical damage, looseness, or contamination.
Check wiring harness: Look for melted insulation, broken wires, or areas rubbing against metal.
Test sensor power and ground: Verify proper voltage reference and grounding.
Check signal wire: Use a multimeter or oscilloscope to confirm output during cranking.
Inspect sensor air gap: Ensure proper spacing between sensor and tone wheel.
Inspect tone wheel: Look for cracks, damage, or missing teeth.
Test distributor pickup (if equipped): Check for resistance and signal output.
Check ICM: If sensor outputs are good but ECU still sees no signal.
Test ECU input: Confirm whether the ECU receives the RPM waveform at the pin.

Pro Tip: Many CKP sensors fail when hot and work again when cold. If the car stalls when hot but starts after cooling down, suspect the crank sensor.

Possible Fixes & Repair Costs

Replace crankshaft position sensor: €40–€120
Replace camshaft position sensor: €40–€100
Replace distributor pickup coil or entire distributor: €80–€250
Repair CKP/CMP wiring or connectors: €50–€150
Replace ignition control module: €80–€180
Replace ECU (rare): €200–€450+

Can I Still Drive With P0322?

No. If the engine does start, it may stall without warning, creating a dangerous situation. Most vehicles will not start at all with P0322 active because the ECU shuts down spark and fuel. Have the vehicle diagnosed and repaired before attempting to drive it.

Last updated: March 1, 2026

Key Takeaways

P0322 means the ECU sees no RPM input signal at all.
CKP/CMP sensors and wiring issues are the most common causes.
The engine may stall suddenly or fail to start.
Repair the issue before driving for safety.

FAQ

Will a bad crankshaft sensor cause P0322?

Yes. It is the most common cause and often results in a no-start or sudden stall.

Why does the tachometer stay at zero?

Because the ECU receives no engine speed signal to display on the gauge.

Can P0322 be intermittent?

Yes. Heat, vibration, or loose wiring can cause intermittent RPM signal loss.

Is P0322 dangerous?

Yes. Loss of engine speed signal can cause sudden, unexpected stalling.

How do I fix P0322?

Start with sensor testing, wiring inspection, and verifying a clean signal. Replace faulty CKP/CMP sensors or repair wiring as needed.

P0322 – Ignition/Distributor Engine Speed Input Circuit No Signal