# Service bulletin 0901222

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

- Type: Service bulletin
- NHTSA id: 10227734
- Published by NHTSA: 2022\-12\-12
- Manufacturer's number: 0901222
- Manufacturer's date: 2022\-10\-01
- NHTSA component: ENGINE AND ENGINE COOLING

## NHTSA's summary

Spark Knock/Engine Symptoms This bulletin involves cleaning the piston heads and cylinder head combustion chambersto resolve a spark knock condition being caused by oil intrusion through the PCV system. The customer may describe a knocking or pinging noise coming from the engine upon acceleration.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2022/MC-10227734-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2022/MC-10227734-9999.pdf)

The document is the manufacturer's. This site does not hold it.

## Components

Engine

## Vehicles listed

- 2020 to 2022 JEEP GLADIATOR
- 2018 to 2021 JEEP GRAND CHEROKEE
- 2022 JEEP GRAND CHEROKEE 4XE
- 2018 to 2022 JEEP WRANGLER

## Recalls for the same vehicles and component

- [2023338](/recalls/tc/2023338.md), 2023-06-08: Engine
- [23V412000](/recalls/nhtsa/23V412000.md), 2023-06-08: ENGINE
- [23V411000](/recalls/nhtsa/23V411000.md), 2023-06-08: ENGINE AND ENGINE COOLING
- [22V865000](/recalls/nhtsa/22V865000.md), 2022-11-23: ENGINE
- [2022584](/recalls/tc/2022584.md), 2022-10-14: Engine
- [22V767000](/recalls/nhtsa/22V767000.md), 2022-10-13: ENGINE; FUEL SYSTEM, GASOLINE:DELIVERY:FUEL PUMP
- [2022217](/recalls/tc/2022217.md), 2022-04-28: Engine
- [22V284000](/recalls/nhtsa/22V284000.md), 2022-04-28: ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:GAS RECIRCULATION VALVE \(EGR VALVE\)
- [2020544](/recalls/tc/2020544.md), 2020-11-12: Engine
- [20V699000](/recalls/nhtsa/20V699000.md), 2020-11-12: ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:GAS RECIRCULATION VALVE \(EGR VALVE\)

## Other bulletins for the same vehicles and component

- [9100363 Rev 3](/bulletins/11036762.md), 2026-09-03, Service bulletin: ENGINE. Turbocharger Kit Please note that many turbo components are serviceable separately and full turbo replacement may not be required. If the turbo is being inspected for: Noise/Rattle: Inspect heat shield fasteners for looseness and check the wastegate actuator/linkage for binding. The actuator kit is serviced separately. Oil Leak: Inspect the turbo oil feed O\-ring area for leaks. O\-ring is serviced separately.
- [113271](/bulletins/11035078.md), 2026-07-18, Service bulletin: ENGINE. CORE – HEATER
- [113270](/bulletins/11035077.md), 2026-07-18, Service bulletin: ENGINE. CORE – HEATER
- [112639](/bulletins/11034912.md), 2026-07-08, Service bulletin: ENGINE. THROTTLE BODY – NONE
- [112640](/bulletins/11034911.md), 2026-07-08, Service bulletin: ENGINE. THROTTLE BODY – NONE
- [18\-062\-26](/bulletins/11034358.md), 2026-07-02, Service bulletin: ENGINE; POWER TRAIN. Flash: Powertrain Control Module \(PCM\) Updates Customers must experience a Malfunction Indicator Lamp \(MIL\) illumination and the vehicle must exhibit/set one or more of the following Diagnostic Trouble Codes \(DTCs\): ● \*\*P0420 \- Catalyst System Efficiency Below Threshold Bank 1. ● P0430 \- Catalyst System Efficiency Below Threshold Bank 2.\*\* ● P0456 \- EVAP System Small Leak. Customers may also comment on one or more of the following: ● \*\*Vehicle fails emissions inspection testing.\*\* ● Pinging/detonation sound from the engine after warm up at 1000\-1500 RPM at low speed. \(EMEA and APAC Only\). ● The vehicle stalls at low speeds and/or coming to a stop This bulletin involves reprogramming the PCM with the latest available software.
- [S2609000009](/bulletins/11034345.md), 2026-07-02, Service bulletin: ENGINE. Check Engine Light \(CEL\) Illuminated with Diagnostic Trouble Code \(DTC\) P0106 Manifold Absolute Pressure Sensor Performance Setting In The Powertrain Control Module \(PCM\)
- [112842](/bulletins/11034335.md), 2026-07-02, Service bulletin: ENGINE. BOLT \- HEX FLANGE HEAD
- [18\-008\-26 REV. B](/bulletins/11033946.md), 2026-06-18, Service bulletin: ENGINE; POWER TRAIN. Flash: Powertrain Control Module \(PCM\) Updates Customers must experience a Malfunction Indicator Lamp \(MIL\) illumination and the vehicle must exhibit/set one or more of the following Diagnostic Trouble Codes \(DTCs\): ● \*\*P0300 \- Multiple Cylinder Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0301 \- Cylinder 1 Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0302 \- Cylinder 2 Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0303 \- Cylinder 3 Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0304 \- Cylinder 4 Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0305\-00 \- Cylinder 5 Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0306\-00 \- Cylinder 6 Misfire \(Active or Stored status set during cold start catalyst heating\).\*\* ● P08A6 – Gear Lever Position Sensor System – Multiple Sensor Correlation. \(Manual Transmission Only\) ● P152F – Engine Hood Switch 2 / Engine Hood Switch 1 Correlation. Customers may also comment on one or more of the following: ● \*\*The vehicle has a rough idle. ● The engine has a miss. ● Noisy valvetrain.\*\* ● "Service Transmission” message on in the Instrument Panel Cluster \(IPC\) due to clutch slip detection. \(Manual Transmission Only\) NOTE: Customers might experience wheel spin or slippage and the PCM could interpreted the wheel spin or slippage as slipping the clutch too much and to avoid clutch damage, the customer may see the message in the IPC. ● Vehicle is in limp home mode. Other software enhancements included: ● Engine oil pump in high pressure mode with cold engine oil to improve valvetrain component reliability. This bulletin involves reprogramming the PCM with the latest available software.
- [18\-050\-26](/bulletins/11031455.md), 2026-04-22, Service bulletin: POWER TRAIN; ENGINE. Flash: Powertrain Control Module \(PCM\) Updates Customers must experience a Malfunction Indicator Lamp \(MIL\) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes \(DTCs\): ● P0300 \- Multiple Cylinder Misfire \- In Active or Stored status set during cold start catalyst heating. ● P0301 \- Cylinder 1 Misfire \- In Active or Stored status set during cold start catalyst heating. ● P0302 \- Cylinder 2 Misfire \- In Active or Stored status set during cold start catalyst heating. ● P0303 \- Cylinder 3 Misfire \- In Active or Stored status set during cold start catalyst heating. ● P0304 \- Cylinder 4 Misfire \- In Active or Stored status set during cold start catalyst heating. ● P0305 \- Cylinder 5 Misfire \- In Active or Stored status set during cold start catalyst heating. ● P0306 \- Cylinder 6 Misfire \- In Active or Stored status set during cold start catalyst heating. Customers may also comment on one or more of the following: ● Check engine illuminates when fueling the vehicle while the engine is running. ● Vehicle has a noticeable misfire. ● Vehicle idles rough. ● Engine noise. NOTE: Noise is heard coming from the valvetrain. In addition, the following software enhancement is available: ● Update to prevent customers from driving their vehicles while the Electric Park Brake \(EPB\) is engaged. Engine torque will be limited to prevent the Rear Drive Unit from being damaged. NOTE: Previously, the EPB would remain engaged without any torque limit which could lead to the Rear Drive Unit being damaged/broken. This bulletin involves reprogramming the PCM with the latest available software.

JSON: [/v1/bulletins/10227734](/v1/bulletins/10227734)

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