VANNE VVT DE DISTRIBUTION VARIABLE

The Ford 5243591 is the Intake Manifold Runner Control (IMRC) Solenoid Valve / Vacuum Solenoid Valve — a 2-wire electromagnetic vacuum control solenoid mounted on the engine bay vacuum harness, controlling vacuum routing to the intake manifold runner control actuator (also known as IMRC, charge motion control valve, swirl flap actuator, or tumble flap actuator). Manufactured by Mitsubishi Electric (K5T81777 supplier reference) and supplied to Ford from approximately 2004 onwards for a wide range of Ford and Mazda gasoline applications with variable intake geometry technology. Two-pin Ford-standard connector with 12V supply from ECU control circuit.

The IMRC solenoid valve operates as part of Ford's variable intake geometry system — technology using a secondary throttle plate ("runner control valve" / "tumble flap") inside the intake manifold to alter air-flow with engine load and RPM. The system has 3 components: (1) ECU-controlled solenoid (the 5243591); (2) vacuum supply hose routing manifold vacuum to solenoid then actuator; (3) mechanical vacuum actuator diaphragm opening/closing the runner control valve.

Operating sequence: at low engine load / RPM, ECU energises the 5243591 solenoid coil, opening vacuum pathway to the actuator diaphragm. Vacuum closes the runner control valve, forcing air through a longer/narrower path that creates optimal swirl/tumble and improves combustion efficiency, fuel economy, and emissions at part-load. At high engine load / RPM, ECU de-energises the solenoid, venting the actuator. Diaphragm spring returns to rest, opening the runner valve for unrestricted air flow and maximum WOT performance.

Three failure mechanisms: (1) solenoid coil burnout from prolonged activation cycling; (2) internal diaphragm leak — rubber seals harden and crack from engine bay heat, allowing vacuum bleed when valve closed; (3) connector pin corrosion from moisture / heat. Associated failures with similar symptoms: vacuum lines crack, actuator diaphragm tears, intake manifold runner control valve carbon-seizes.

Note: ok.parts listing shows HS 8543.70 (electrical machines with individual functions) consistent with the generic "sensor" categorisation. Vacuum solenoid valves for intake manifold runner control are correctly classified under HS 8481.20 (valves for oleohydraulic or pneumatic transmissions), which is the standard HS code for automotive vacuum solenoid valves, EGR solenoids, and similar pneumatic control components. Confirm exact 10-digit subheading with your customs broker. Commercial invoice description: electromagnetic vacuum solenoid valve (IMRC actuator control), 12V DC automotive engine management component for spark-ignition gasoline engine intake manifold runner control system.

Does NOT fit: Ford diesel engines (Duratorq TDCi 1.6 / 1.8 / 2.0 / 2.2L) — use different EGR / boost control solenoids; Ford Focus Mk1 (pre-2004) — different intake manifold design without IMRC system; Ford Focus Mk3 (2010+) — uses different IMRC actuation system, different part references; Ford Fiesta (any generation) — different engine architecture; Ford US-market vehicles outside Focus/Mondeo/Galaxy/S-MAX/C-MAX family — verify by Ford USA catalogue; EcoBoost engines (1.0L / 1.6L / 2.0L EcoBoost direct-injection turbo) — different intake management system, different IMRC references; Mazda non-Ford-era engines (SkyActiv platform 2012+) — different intake control architecture. Always verify by reading the OEM number stamped on existing solenoid or checking Ford parts catalogue by VIN before ordering. The 5243591 covers specifically Ford C1/CD platform 1.8L / 2.0L Duratec naturally-aspirated petrol engines built 2004-2014/15.

Difficulty: Easy. Estimated time: 15–30 minutes. The IMRC solenoid is engine-bay-mounted with easy access on most Ford applications. Always check associated components — vacuum lines, IMRC actuator diaphragm, and intake manifold runner control valve — before solenoid replacement, as solenoid failure is often caused by associated component failure increasing solenoid duty cycle.

1. 1
   Locate IMRC solenoid valve in engine bay — typically mounted on a bracket near the intake manifold or firewall, with vacuum hoses routed on intake manifold port + IMRC actuator port. Wiring connector is a 2-pin Ford standard solenoid connector.
2. 2
   Disconnect wiring connector — press release tab + pull connector body straight off. Inspect for corrosion, oil contamination, or damaged pins.
3. 3
   Note vacuum hose routing and orientation by photograph BEFORE disconnecting hoses. Each hose has a specific port (vacuum supply from intake manifold vs vacuum delivery to actuator) — mis-routing prevents correct operation.
4. 4
   Disconnect vacuum hoses from solenoid valve ports. Inspect hoses for cracking, hardening, or kinks — replace any showing degradation.
5. 5
   Remove solenoid valve mounting bolt(s) — typically 1-2 small bolts (M5 / M6) retaining solenoid to bracket. Extract solenoid from bracket. Some applications use a clip-fit retention rather than bolts.
6. 6
   Compare new solenoid to old — verify dimensions, vacuum port positions, connector pinout, and mounting bracket geometry match exactly. Confirm OEM 5243591 or verified cross-reference from Ford supersession list.
7. 7
   Install new solenoid valve in bracket position. Torque mounting bolts to OEM specification (typically 5-8 Nm for small mounting bolts — consult Ford service manual or TIS / forscan for exact torque).
8. 8
   Reconnect vacuum hoses to correct ports (per photographed routing). Verify hose tightness on solenoid barbs — loose connections allow vacuum leaks that prevent correct IMRC operation. Replace hose clamps if showing corrosion / fatigue.
9. 9
   Reconnect wiring connector with positive click engagement. Visually verify connector seal lip seats around mating connector housing for moisture protection.
10. 10
    Clear stored DTCs with Ford IDS / forscan or generic OBD-II scanner. P2004-P2010 codes should clear immediately upon solenoid replacement and activation cycle.
11. 11
    Test drive vehicle through full RPM range — idle, part-load cruise, and WOT acceleration. Verify: no return of IMRC fault codes, smooth power delivery during light-throttle acceleration, normal WOT power, no audible vacuum hiss from engine bay.
12. 12
    Re-scan for DTCs after drive cycle — confirm no return of IMRC fault codes; verify fuel trim values stable; ensure long-term fuel trim remains within Ford specification (typically -10% to +10% at warm operating conditions).