CarFaultIQ

P0325

P0325: Knock Sensor Circuit Bank 1

Updated Last reviewed December 26, 2026By CarFaultIQ Editorial Team

Verify with official recall databases, service records, a mechanic inspection, and local market data before relying on this summary.

At a glance

Quick diagnostic answer

The computer sees a fault in the knock sensor or its circuit.

SeverityModerate UrgencyUrgency not yet verified EvidenceSource notes available
OBD code
P0325
System/category
Sensors & Circuits
Severity
Moderate
Structured severity term
Urgency
Urgency not yet verified
Can I drive?
Drive with caution
Drive gently and avoid heavy throttle until it is checked; if the engine knocks, overheats, or loses power, stop and get help.
Repair/cost band
$$ · Moderate
Often a moderate repair; access can make labor higher on some engines.
Vehicle applicability
Generic OBD-II code across many makes and models; confirm service information for the exact vehicle.
Current applicability note is free text

Computed rule output may be more cautious than stored content and is never used to soften safety-critical risks.

Short answer

P0325 usually means the computer sees a fault in the knock sensor or its circuit. Drive gently and avoid heavy throttle until it is checked; if the engine knocks, overheats, or loses power, stop and get help. Check for wiring damage, connector corrosion, and other engine-noise or overheating symptoms before replacing the sensor.

SeverityModerateDrive?Drive with cautionRepairProfessional

Key takeaways

  • P0325 points to a detected condition, not an automatic parts order.
  • Drive gently and avoid heavy throttle until it is checked; if the engine knocks, overheats, or loses power, stop and get help.
  • Check for wiring damage, connector corrosion, and other engine-noise or overheating symptoms before replacing the sensor.
  • Use scan data and a visual inspection before replacing sensors.

At a glance

Question Short answer Next move
Can I drive? Drive gently and avoid heavy throttle until it is checked; if the engine knocks, overheats, or loses power, stop and get help. Keep trips short if it runs normally; stop if symptoms get worse.
Likely cost Often a moderate repair; access can make labor higher on some engines. Get a written diagnosis before buying parts.
Check first Check for wiring damage, connector corrosion, and other engine-noise or overheating symptoms before replacing the sensor. Start with the cheap visible checks.

Can I still drive with this?

Drive with caution

Drive gently and avoid heavy throttle until it is checked; if the engine knocks, overheats, or loses power, stop and get help.

SeverityModerate

Moderate

Diagnostic flow

  1. What it meansThe computer sees a fault in the knock sensor or its circuit.
  2. Check this firstListen for real pinging or knocking under load.
  3. Likely causeFailed knock sensor
  4. Can you drive?Drive with caution

P0325 does not mean your engine is definitely knocking. It means the knock sensor circuit is not giving the computer a trustworthy signal.

That sensor helps the computer protect the engine from detonation, which is the sharp pinging knock that can damage parts under load.

Check for wiring damage, connector corrosion, and other engine-noise or overheating symptoms before replacing the sensor.

Structured DTC reference

What P0325 means

A fault in the knock sensor circuit

A trouble code identifies the circuit or monitored condition that failed its test. It does not, by itself, identify the failed part or prove the same cause on every vehicle.

Cause categories to discriminate

  • Failed knock sensor

These are structured diagnostic hypotheses, not a parts-replacement list. Vehicle context, symptoms, operating conditions, and test results determine which remain supported.

Severity and drivability

The code alone is not enough to assign one universal severity or “safe to drive” answer. Stop driving for loss of braking or steering, severe overheating, oil-pressure loss, a fuel leak or fire risk, or any rapidly worsening safety symptom.

Add the symptom contextChoose the vehicle

What it means

The computer sees a fault in the knock sensor or its circuit.

Common symptoms

  • Check-engine light
  • Reduced power
  • Pinging under load
  • Poor fuel economy

Likely causes

  • Failed knock sensor
  • Damaged sensor wiring
  • Connector corrosion
  • Real engine knock from overheating or poor fuel

Diagnosis steps

  1. Listen for real pinging or knocking under load.
  2. Check coolant temperature and oil level.
  3. Inspect knock sensor wiring and connector condition.
  4. Confirm the circuit fault with service information before replacing the sensor.

What a mechanic should check

A mechanic should separate a circuit fault from real detonation and inspect wiring before replacing a buried knock sensor.

Vehicle applicability

Generic OBD-II code across many makes and models; confirm service information for the exact vehicle.

Repair actions / cost band

$$ · Moderate

Often a moderate repair; access can make labor higher on some engines.

P0325 — vehicles with official records naming this code

P0325 is named in NHTSA-published manufacturer communications or investigations for 5 vehicle families, including:

A code named in a manufacturer communication means the document refers to it for those vehicles. It is not a diagnosis of any car, and it does not mean the code is common on that vehicle.

Frequently asked questions

What does P0325 mean?

the computer sees a fault in the knock sensor or its circuit.

Is P0325 safe to drive with?

Drive gently and avoid heavy throttle until it is checked; if the engine knocks, overheats, or loses power, stop and get help.

What should I check first?

Check for wiring damage, connector corrosion, and other engine-noise or overheating symptoms before replacing the sensor.

Continue exploring

Related codes

Known faults that trigger this code

Related symptoms

Keep going

Next diagnostic step

Check warning lights Use the dashboard light to decide what to do now. Trace the symptom Match what you can see, hear, smell, or feel. Find vehicle coverage Check model-year problem windows and related faults.

Source & evidence notes

  • What this is based on: generic OBD-II code references, EPA OBD background, and standard diagnostic practice.
  • This page is not based on complaint counts, repair-cost averages, or CarFaultIQ owner submissions.
  • Sources used: CarParts P0325 reference; US EPA OBD background.
  • URLs: https://www.carparts.com/blog/p0325-code-knock-sensor-malfunction-sensor-1-bank-1/; https://19january2021snapshot.epa.gov/state-and-local-transportation/vehicle-emissions-board-diagnostics-obd_.html.
  • Confirm the exact diagnosis with live scan data, the owner manual, or service information for the specific vehicle.