P0507 code what is the fix?

Question

Engine rpm crazy high. Changed IAC no change. Can pinch off air supply hose idle drops.

Answer 1

P0507 Idle control system RPM higher than expected

P1506 Idle air control overspeed error

Check for vacuum leaks,especially at the throttle body and intake manifold ,check also the PCV hose for rupture and the PCV valve itself. Another vacuum that can cause over speed is ,the EVAP system for a stuck open valve,This will be at the canister purge area. If it ll check out and there is no vacuum leaks causing the high RPM and no other codes, Disconnect the IAC valve harness if there is no RPM change, the ECM is at fault.