P0327 on Hyundai: How to Diagnose & Fix
Knock Sensor 1 Circuit Low Input (Bank 1)
1 Hyundai model · 1 documented issue · $200-$1,200 repair
P0327 on Hyundai by model: symptoms, diagnosis and fix
Some naturally aspirated 2.0L Veloster owners report check-engine lights, rough running, and reduced-power behavior tied to knock sensor activity or engine protection logic. While not as notorious as older Hyundai engine campaigns, the symptom pattern is documented enough to appear in owner complaints and service discussions: the car may suddenly feel flat, limit RPM, or illuminate the MIL even when no obvious mechanical noise is present. In some cases the issue is sensor-related; in others it requires ruling out genuine detonation, wiring faults, or software sensitivity.
Common Symptoms
- check engine light
- reduced power
- engine feels flat or limited
- intermittent rough running
- RPM limited
How to Fix
Scan for knock-sensor and misfire-related codes, inspect harness routing and connector condition, and verify fuel quality and ignition system health. If no mechanical problem is found, dealers may update software or replace the knock sensor/harness as needed. Persistent knock-related faults should not be ignored because the ECU may be actively protecting the engine from perceived abnormal combustion.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Genuine Hyundai knock sensor assemblyOEMHyundai 39250-2E000
knock-sensor replacement after testing confirms a sensor/circuit fault and mechanical knock is ruled out Fitment/availability: Hyundai 39250-2E000 is cataloged for 2019-2021 Veloster with the naturally aspirated DOHC-MPI engine. Confirm …
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Sources for this issue (1)
P0327 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0327 mean on a Hyundai?
P0327 stands for "Knock Sensor 1 Circuit Low Input (Bank 1)." This code means the knock sensor on engine bank 1 sent a voltage signal that was lower than the expected range. The knock sensor is a small vibration microphone bolted to the engine block that listens for the 'pinging' of abnormal combustion (detonation), letting the computer retard ignition timing to protect the engine. A low-input reading usually points to an electrical problem — a fault in the sensor, its wiring, or connector — rather than actual knock. With the sensor compromised, the engine may run with safer, less efficient timing, causing slightly reduced power or fuel economy. On Hyundai it is documented across 1 model: Veloster.
What are the most common causes of P0327?
The most common causes of P0327 are: Faulty knock sensor (Bank 1, Sensor 1), Damaged, shorted-to-ground, or corroded sensor wiring, Loose or corroded sensor connector, Improperly torqued/loose sensor mounting, Open or high-resistance signal circuit, Wiring shielding or grounding problem, Faulty engine control module (PCM) — rare. The specific cause varies by vehicle.
How much does it cost to fix P0327 on a Hyundai?
Published repair estimates on Hyundai range from $200 to $1,200 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0327 on a different make?
View P0327 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.