P1326 Hyundai and Kia: the knock sensor detection system (KSDS) has picked up vibration that matches abnormal connecting rod bearing wear

Knock sensor detection system (KSDS) alert / knock signal range-performance (Hyundai/Kia)

P1326 in short

On Hyundai and Kia vehicles, P1326 means the knock sensor detection system heard vibration matching connecting rod bearing wear. The check engine light blinks and the car limits power and rpm. Drive only as far as the nearest dealer: the inspection may lead to engine replacement, often under extended warranty.

After engine failures on Theta II and some other GDI engines, Hyundai and Kia added software called the Knock Sensor Detection System (KSDS). It uses the existing knock sensor to listen for the vibration pattern a wearing connecting rod bearing makes before the engine fails.

When it hears that pattern it stores P1326, makes the check engine light blink continuously (with a chime on some models) and puts the engine in a protection mode: slower acceleration, lower top speed and rpm held to about 1800-2000. Hyundai says brakes, steering and airbags keep working and the car can be driven a limited distance to a dealer.

At the dealer, Hyundai's and Kia's bulletins tell technicians to inspect the engine and either replace it or update the ECU software, depending on what they find. Hyundai extended engine warranty coverage on affected models; whether your car is covered depends on its VIN.

Pick your make

P1326 is a manufacturer-specific code: its meaning depends on who built the car.

Other makes: meaning not verified. Check with a scan tool that reads manufacturer definitions.

Most likely causes

  1. Connecting rod bearing wear or damage

    Supported by vehicle data
    Why it ranks here
    This is what the KSDS is designed to detect. Hyundai bulletins describe P1326 with engine noise or no-start from connecting rod bearing wear, and Kia bulletins give engine replacement instructions when P1326 sets.
    What would change this
    Rises with knocking from the bottom of the engine, oil consumption or metal in the oil; dealer inspection confirms it.

  2. Engine monitoring software needing a further update

    Supported by vehicle data
    Why it ranks here
    Hyundai issued a bulletin for 2016-2021 Tucson 2.0L with P1326 continuing after the first KSDS update, and its inspection bulletins allow an ECU update when the engine passes inspection.
    What would change this
    Rises if the dealer inspection finds no bearing damage.

What to test first

Start at step 1. Each result tells you what it means and where to go next.

  1. Note whether the check engine light is blinking, the car is limited in power and rpm, and whether you hear knocking. Do not keep driving normally.

    Low risk

  2. Have a Hyundai or Kia dealer run the P1326 inspection procedure from the bulletin for your model and check campaign and warranty status by VIN.

    Best left to a shopTool: dealer diagnostic equipment

    Warning:Engine inspection for bearing damage needs dealer tools and procedures; do not attempt it at home.

Symptoms

  • Check engine light blinking continuously Gets more serious: stop and have it checked.
  • Reduced power, slow acceleration and an rpm limit Gets more serious: stop and have it checked.
  • Knocking noise from the engine Gets more serious: stop and have it checked.
  • Engine will not crank or start Gets more serious: stop and have it checked.

Compare with: Check engine light with loss of power

How to fix

We don't give DIY repair steps for a Stop code. Get the car inspected before you drive it; the tests above help you understand what a technician will check.

On your vehicle

Hyundai

  • 2011–2019 · 2.0L T-GDI, 2.4L GDI

    Supported by vehicle data

    On 2011-2019 Sonata, Santa Fe Sport, Tucson and Veloster with 2.0L T-GDI or 2.4L GDI engines, Hyundai inspects for connecting rod bearing damage when P1326 sets and replaces the engine or updates the ECU. Hyundai extended engine coverage to 10 years/120,000 miles for 2011-2018 Sonata and 2013-2018 Santa Fe Sport; check by VIN.

  • 2016–2021 · Tucson · 2.0L

    Supported by vehicle data

    On 2016-2021 Tucson 2.0L, a further bulletin covers P1326 that keeps returning after the first software update.

  • 24-01-068HStatus unverified

    Engine monitoring logic update: knock sensor software to detect abnormal bearing noise

    2010–2021sonata-hybrid, veloster, elantra-gt, tucson, santa-fe · issued · NHTSA 11006829

    Campaign bulletin: the updated knock sensor software blinks the MIL, enters Engine Protection Mode and records DTC P132600 when it detects abnormal bearing noise, so the car can be driven to the nearest dealer.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • 22-01-023HStatus unverified

    Check engine light with P1326 and/or engine noise from connecting rod bearing wear

    2010–2019sonata-hybrid, elantra, veloster, tucson, santa-fe · issued · NHTSA 10210206

    Inspect the engine, then replace it and/or update the ECU software depending on the result.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • 22-01-033HStatus unverified

    P1326, abnormal noise or no crank/no start on 2.0L T-GDI and 2.4L GDI

    2011–2019sonata, tucson, santa-fe-sport, veloster · 2.0L T-GDI, 2.4L GDI · issued · NHTSA 10211669

    Inspect the engine, then replace it or update the ECU software depending on the result.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • 24-EM-002HStatus unverified

    Continued P1326 after the engine monitoring logic update

    2016–2021tucson · 2.0L · issued · NHTSA 10252363

    Procedure for 2016-2021 Tucson 2.0L that keep setting P1326 after the Service Campaign 966 ECU update.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Kia

  • 2014–2019 · 2.4L GDI, 2.0L T-GDI

    Supported by vehicle data

    On 2014-2019 Optima, Sorento and Sportage with Theta II engines, Kia gives engine replacement instructions when P1326 sets after the KSDS update.

  • PI1802YZStatus unverified

    Product improvement campaign: engine replacement instructions for DTC P1326

    2014–2018optima, sorento, sportage · Theta II 2.4L GDI, Theta II 2.0L T-GDI · issued · rev. R7 · NHTSA 10252085

    If a car returns with P1326 (Knock Signal Range/Performance) after the KSDS ECU logic update, follow these engine replacement procedures. Theta II engines.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • PI1805YZStatus unverified

    Product improvement: procedures if P1326 returns after KSDS installation

    2019optima, sorento, sportage · 2.4L GDI, 2.0L T-GDI · issued · NHTSA 10249001

    Same P1326 procedures for 2019 Optima, Sorento and Sportage with the 2.4L GDI or 2.0L T-GDI.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • P0325Knock sensor 1 circuit fault (bank 1 or single sensor)

    Same system Supported by vehicle data

    P1326 uses the existing knock sensor to listen for connecting rod bearing wear; it is not a knock sensor circuit fault like P0325.

All Ignition and engine position sensors codes

P1326 questions

Can I drive with P1326?

Only as far as the nearest Hyundai or Kia dealer, gently. The car is in a protection mode because the system detected bearing wear that can lead to engine failure. If the engine knocks loudly or will not start, have it towed.

Is P1326 covered by warranty?

Often, but it depends on the VIN. Hyundai extended engine coverage on many affected models (10 years/120,000 miles for 2011-2018 Sonata and 2013-2018 Santa Fe Sport), and both makers run campaigns for these engines. Ask the dealer to check your VIN.

Is P1326 just a bad knock sensor?

No. The knock sensor is only the microphone. P1326 means the software heard vibration matching connecting rod bearing wear, so the dealer inspects the engine itself rather than swapping the sensor.

Sources and review

  1. Hyundai 24-01-068H: Engine monitoring logic update (knock sensor detection software, Service Campaign 966 family) — Hyundai Motor America / NHTSA ,
  2. Hyundai 22-01-033H: DTC P1326, abnormal noise or no crank/no start, 2.0L T-GDI and 2.4L GDI — Hyundai Motor America / NHTSA ,
  3. Hyundai Issues Recall and Engine Software Update for Certain Sonata and Santa Fe Sport Vehicles — Hyundai Motor America (press release via PR Newswire) ,
  4. Hyundai 22-01-023H: Check engine lamp with DTC P1326 and/or engine noise from connecting rod bearing wear — Hyundai Motor America / NHTSA ,
  5. Kia PI1802Y/Z (R7): Engine replacement instructions for DTC P1326 after Knock Sensor Detection System installation — Kia America / NHTSA ,
  6. Hyundai 24-EM-002H: Continued DTC P1326 after the engine monitoring logic update, 2016-2021 Tucson 2.0L — Hyundai Motor America / NHTSA ,
  7. Kia PI1805Y/Z: Procedures if DTC P1326 returns after KSDS installation, 2019 Optima, Sorento, Sportage — Kia America / NHTSA ,
Last reviewed
Written by
Saurabh K.
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