P0325
Ignition/Distributor Engine Speed Input Circuit Intermittent
Powertrain Ignition System Crankshaft sensor signal 🟡 Moderate — Fix within a week
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What This Actually Means
In plain language — no jargon

Your engine's crankshaft position sensor is sending an unreliable signal to the computer, like a radio that keeps cutting in and out. The ECU can't consistently read engine speed, which throws off ignition timing and fuel injection.

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Symptoms You May Notice
3 known symptoms for this code
Engine stalling or hesitation during acceleration
Check Engine Light blinking or illuminated
Rough idle or difficulty starting
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Embedded Systems Insight
What the ECU/ECM is actually computing

The ECU monitors the crankshaft position (CKP) sensor signal for consistent pulse patterns that indicate engine RPM and timing. When the signal drops out intermittently or becomes erratic, the ECU cannot reliably calculate ignition advance and fuel injection duration. A healthy signal should maintain steady frequency within expected RPM ranges.

Voltage & Parameter Thresholds

Parameter Normal Range Fault Condition
CKP Signal Frequency Stable pulses matching RPM Intermittent dropouts or erratic pulses
Signal Voltage 0.2-5V oscillation Voltage spikes or complete signal loss
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Diagnostic & DIY Fix Guide
Check these in order — from cheapest to most complex
1
Engine harness connector
Inspect and clean the CKP sensor connector for corrosion or loose pins.
2
CKP sensor wiring
Check for damaged insulation, pinched wires, or intermittent breaks along the sensor harness.
3
Crankshaft position sensor
Replace the CKP sensor if wiring is intact but signal remains intermittent.