What part is responsible for a P0505 Idle control system malfunction reading in a 1997 geo prism?

Answer 1

The P0505 code indicates a malfunction in the Idle Air Control (IAC) system. In a 1997 Geo Prism, this typically points to issues with the IAC valve itself, which regulates airflow during idle to maintain a stable engine RPM. Other potential causes include vacuum leaks, wiring issues, or problems with the Engine Control Module (ECM) that manages the IAC. Diagnosing the exact cause often requires checking the IAC operation, inspecting for leaks, and ensuring proper electrical connections.