Standard Ignition AC291 Idle Air Control Valve

Idle Air Control Valve for Ford Explorer and Mercury Mountaineer

Standard Ignition AC291 is an idle air control valve for specific 1997-1998 Ford Explorer and 1998 Mercury Mountaineer applications. It regulates bypass air at idle to help maintain stable engine speed when loads change, such as when the A/C is on or the engine is warming up.

Key Features

• Square connector shape for the listed applications
• 1 air control port and 2 terminals
• Gaskets included for installation on the matching throttle body setup
• Polymer-blended magnet helps control pintle movement and airflow accurately
• High-strength stepping motor delivers strong output torque
• Shielded ball bearing resists environmental contamination for longer service life
• Load-tested actuator for added durability and consistent operation
• Standard Ignition AC291 cross-references Delphi CV10112 and DENSO Auto Parts 150-2004 for the same application

Detailed Description

Standard Ignition AC291 is built for direct replacement use on 1997-1998 Ford Explorer and 1998 Mercury Mountaineer models with the listed idle air control valve configuration. The design uses a precision magnet and stepping motor assembly to manage idle airflow with consistent response, while the sealed bearing construction helps protect the motor from contamination. If you are replacing a worn Ford Explorer idle air control valve or a Mercury Mountaineer idle speed control valve, this part number provides the fitment and connector style needed for the specified vehicles.

Standard Ignition AC291 is a practical choice when diagnosing idle quality concerns on Ford Explorer and Mercury Mountaineer vehicles that match the OE-style connector and port layout.

Common Issues This Part Can Help Address

• Unstable or fluctuating idle speed
• Stalling when coming to a stop
• High idle after startup or during warm-up
• Idle speed changes when accessories are switched on
• Airflow control problems caused by a worn IAC valve

Installation Notes and Tips

Verify connector shape, terminal count, and port layout before installation. Clean the throttle body and mating surfaces, and install the included gasket to help maintain a proper seal. After replacement, clear any stored idle-related fault codes and allow the engine to relearn idle strategy if required by the vehicle.

Quality Assurance

Standard Ignition manufactures this idle air control valve with high-grade materials and tests the actuator under load to confirm proper force output. The motor assembly and contamination-resistant bearing are engineered for dependable operation in demanding underhood conditions.