The engine may idle too high, too low, or surge/struggle at a standstill.
If on a dCi engine, check the exhaust pressure sensor for high voltage readings, particularly with the ignition on. p158b renault
Disclaimer: P158B is a complex code. If you are not comfortable working with high-voltage sensors or delicate wiring, it is recommended to have the car diagnosed by a professional Renault technician. To help narrow down the exact cause, let me know: The engine may idle too high, too low,
Understanding and Fixing Renault Fault Code P158B If your Renault’s dashboard has lit up with a Check Engine light, and a diagnostic scanner reveals the code , you are likely dealing with a manufacturer-specific powertrain issue. While OBD-II scanners sometimes provide generic definitions, this code often relates to internal diagnostics within the idle-speed control system or exhaust pressure management, particularly in Renault and Dacia models. If you are not comfortable working with high-voltage
Cleaning corrosion from connectors with electrical cleaner.
Diagnosing the P158B code requires a systematic approach to check both the component and the wiring.
Test the actuator for proper operation. If the wiring is sound, the actuator likely needs replacement. Potential Fixes