2001 Ford Escort P1520 Error: Intake Manifold Runner Circuit Failure Diagnosis and Fixes
I recently encountered a P1520 error code on my 2001 Ford Escort. The diagnostic reading indicates 'Intake Manifold Runner Circuit Failure' — specifically, the Engine Control Module (ECM) has detected an open or shorted condition in the Intake Manifold Runner Control (IMRC) circuit. Common causes include electrical shorts or opens within the IMRC wiring or actuator. The technician at AutoZone advised contacting a Ford dealer or certified mechanic, but since I purchased this vehicle used, I'm unsure of any affiliated dealerships. Can anyone provide guidance on how to diagnose or repair this issue? Additionally, my car has been idling roughly compared to its previous behavior, which may be related to the P1520 fault.
Check the plastic grommet that secures the intake manifold runner actuator to the runner itself — these are prone to cracking or breaking. Also ensure there is no mechanical binding in the system. On most Ford models, you can observe the movement of the actuator arms by abruptly snapping the throttle while the engine is running.