P0505 Defective Idle Air Control Motor, Intake Manifold Vacuum leaks, Carbon buildup in the Throttle Body air passages
Check the Idle Air Control (IAC) motor: The IAC motor controls the idle speed of the engine. If it is defective, it needs to be replaced.
Inspect for vacuum leaks: Vacuum leaks can cause the engine to idle poorly. Check for any damaged or disconnected vacuum hoses, and repair or replace them as necessary.
Clean the Throttle Body: Carbon buildup in the throttle body air passages can also cause the engine to idle poorly. Remove the air intake hose from the throttle body, and clean the throttle body and air passages using a throttle body cleaner.
Check the Throttle Position Sensor (TPS): The TPS is used to determine the throttle plate position. If it is not functioning properly, it can cause issues with the engine idle. Check the TPS for proper operation and replace if necessary.
Inspect the PCV system: The Positive Crankcase Ventilation (PCV) system recirculates gases from the engine back into the intake manifold. If it is clogged or not functioning properly, it can cause idle issues. Inspect the PCV system and replace any damaged or clogged components.
Check for any other codes: It is important to check for any other codes that may be present, as they could be related to the P0505 code. Addressing those codes may also resolve the P0505 code.
