Ignition & misfire · Powertrain · generic (SAE-defined)
P0328: Knock Sensor 1 Circuit High (Bank 1 or Single Sensor)
P0328 means knock sensor 1 (bank 1 or single sensor) is sending a signal higher than expected, from a wiring fault, a faulty sensor, or excessive engine noise.
Standard title per SAE J2012 / ISO 15031-6 · Updated 2026-11-07 · By CarWhere Research
How P0328 sets
The powertrain control module (PCM) expects knock sensor 1 to output a signal within a defined range. When the signal stays above the upper limit, which can come from a short to voltage, electrical noise, or excessive mechanical noise, P0328 sets. Exact limits are manufacturer-specific.
Common causes of P0328
Roughly most likely first; the actual cause depends on the vehicle and needs testing to confirm.
- Knock sensor wiring shorted to voltage or picking up interference
- Failed knock sensor
- Genuine detonation from low-octane fuel, carbon buildup, or overheating
- Loose engine components creating noise, such as heat shields or accessory brackets
- Internal engine noise from worn bearings or valvetrain
P0328 symptoms
- Check engine light on
- Pinging or knocking under acceleration
- Reduced power
- Lower fuel economy
How P0328 is diagnosed
- Review freeze frame data, including engine load and coolant temperature.
- Listen for real knocking or mechanical noise and check fuel grade.
- Inspect wiring for shorts and routing near ignition components.
- Test the sensor signal with an oscilloscope or scan tool.
- Check for loose heat shields or brackets near the sensor.
Typical fixes for P0328
- Repair shorted or poorly routed wiring
- Replace the knock sensor
- Use the manufacturer-recommended fuel grade
- Repair mechanical noise sources
- Address carbon buildup or overheating causing detonation
Replace parts only after testing confirms the cause — a code names the circuit or condition that failed a check, not necessarily the faulty part. We don’t publish per-repair prices; for what households actually spend on upkeep, see car repair costs.
Related codes & warning lights
P0328 FAQ
What does code P0328 mean?
P0328 means knock sensor 1 (bank 1 or single sensor) is sending a signal higher than expected, from a wiring fault, a faulty sensor, or excessive engine noise. The standard definition is "Knock Sensor 1 Circuit High (Bank 1 or Single Sensor)."
Can I drive with a P0328 code?
Typically yes, with care. The computer may pull ignition timing, reducing power; if you hear knocking or pinging, avoid heavy acceleration and check fuel grade before continuing.
Does P0328 mean my engine is actually knocking?
Not always. It can be a wiring or sensor fault, but genuine knock or mechanical noise can also push the signal high, so both should be checked.
Will higher-octane fuel fix P0328?
If the engine requires premium fuel and has been running on regular, switching may help. It will not fix a wiring or sensor fault.
Keep researching
Engine guides by brand (known issues, specs)
More ignition & misfire codes
Sources
- SAE J2012 — Diagnostic Trouble Code Definitions (standard code titles)
- ISO 15031-6 — Road vehicles: communication between vehicle and external equipment for emissions-related diagnostics, Part 6: Diagnostic trouble code definitions
- U.S. EPA — Vehicle Emissions Inspection and Maintenance (I/M) programs
- U.S. EPA, 40 CFR 86.1806-17 — Federal onboard diagnostics requirements for light-duty vehicles
General information written by CarWhere Research, not a diagnosis of your vehicle. Manufacturers can add their own sub-definitions and test conditions; confirm with the factory service information for your year, make and model. Before paying for a repair, check NHTSA for open recalls and your warranty booklet: federal law requires an emissions warranty on major emission-control parts such as the catalytic converter and engine computer.