P0327

Knock Sensor 1 Circuit Low (Bank 1 or Single Sensor)

Car Fault Codes Ignition & misfire

Can you still drive? Yes, normally

Who can fix it? Needs a workshop

Typical repair time 30 minutes – 4 hours

Typical cost SAR 100 to 900

What it means

The signal from knock sensor 1 on bank 1 is weaker than the minimum the engine computer expects. This usually comes from an open wire, a short to ground or a loose sensor that does not pass on vibration, and the computer retards ignition timing as a precaution.

Symptoms4

Check engine light on.
Weaker acceleration.
Slightly higher fuel consumption.
Often no other clear symptoms.

Possible causes5

Open sensor wiring or a disconnected or corroded connector.
Signal wire shorted to ground through damaged insulation.
Loose sensor or one tightened below the required torque, so it does not pick up vibration well.
Failed sensor.
Engine computer fault (rare).

How to diagnose5

Inspect the connector and wiring for breaks, corrosion or damaged insulation touching the engine.
Check wiring continuity between the sensor and the computer, and make sure there is no short to ground.
Measure sensor resistance and compare it with the manufacturer specification.
Confirm the sensor torque.
Check the sensor signal while lightly tapping near it if an oscilloscope is available.

How to fix5

Reconnect and clean the connector, and repair broken or damaged wires.
Retighten the sensor to the correct torque.
Replace the knock sensor if it is proven faulty.
Replace the sensor harness if the damage cannot be repaired.
Clear the codes, drive and confirm the code does not return.

Repair cost

0–500

500–2,000

2,000–5,000

5,000+

In Saudi riyals; the highlighted part is the expected range for this fault.

The cost is low for a connector or wire repair, and reaches the top of the range when a sensor that requires removing engine parts is replaced.

Prices are rough estimates for common cars at independent workshops and vary with the car and the source of the part.
Prices last updated: September 2026

Frequently asked questions

Can a loose sensor cause this code?

Yes. The sensor picks up vibration through its mounting surface, so if it is loose its signal weakens and the code sets even though the sensor is fine.

Is the code harmful to the engine?

Usually not, since the computer retards timing as a precaution, but power and economy suffer, and the engine may lose knock protection if it is left too long.

This guide is for information only and does not replace an inspection by a qualified technician. If the fault involves brakes, steering, engine temperature, electrics or refrigerant, do not attempt the repair yourself.

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