It is important to know the history of the throttle valve and the impact it had on automotive design in the 1990s. The design of vehicles produced before 1990 was relatively simple compared to the computer-controlled models we see today. A cable directly connected to an accelerator pedal could control the throttle. The ‘Electronic Throttle Control Technology‘ of today, however, is made up of an accelerometer pedal position sensor and a throttle body that’s electronically controlled. It also includes two embedded sensors to determine correlation factors. This code is applicable to all vehicles produced between 1996 and the present. This code indicates that the Engine Control Module detected a fault in the D or E circuits which prevents the throttle from closing and opening properly. This code may be displayed under different names, even though it indicates the same fault across all models and makes. Infiniti may define it as a fault relating to the ‘Throttle Position Sensor Circuit Range/Performance’. Hyundai may indicate a ‘Electronic Throttle Control System Fault Power Management’.
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What are the symptoms of fault code P2138?
The fault code P2138 can manifest in several ways. Along with the fault code, an engine fault light may illuminate. While the vehicle is moving, you may feel sudden power loss in the engine. The engine can also stall after the vehicle has stopped completely. A stuck throttle valve can cause acceleration problems.
- Engine fault light illuminates
- The engine may not start.
- The engine may not start
- Loss of power during acceleration
What are the causes of fault code P2138?
The fault code P2138 can be caused by several things. The code may be caused by corroded, loose or short-circuited cable connections. Deformation of the throttle can also cause gear rotation problems. One or more sensors, or even the throttle body itself, may fail. The engine management computer could also be malfunctioning.
- A defective throttle body motor
- Cable or connector damaged in connection with throttle body motor
- Faulty throttle sensor
- Faulty engine control module
How to Fix Error Code P2138?
All intervention procedures should be performed with extreme care, as the throttle control system is highly sensitive. Inspection of all components within the throttle body is required. The throttle pedal position sensor is the only component outside of the body. All components are checked and the cover is removed in order to inspect for wear and tear. Circuit problems are checked on the throttle position sensor, connectors, cables and other components. Replace suspect and defective parts. If the problem is not caused by the throttle body or its components, then the Engine Control Module should be inspected and replaced as necessary.
Note: Never attempt to open the throttle valve manually in the electronic throttle body using your hand or other tools. This can cause serious damage to the electronic throttle motor, and may prevent the vehicle’s operation.
