Standard Ignition AC399 Idle Air Control Valve

Idle Air Control Valve for BMW and Saab

Standard Ignition AC399 is an idle air control valve for select BMW and Saab applications. It is built with 2 hose connectors, 3 blade terminals, and a direct-fit style layout for vehicles that use this configuration.

Key Features

• Idle air control valve for fuel injection system applications
• 2 hose connectors for the specified intake and bypass routing
• 3 blade terminals for electrical connection
• Fits select BMW 323i, 325i, 330i, X5, and Z4 applications
• Fits select Saab 900 and 9-3 applications
• Standard Ignition AC399 part number for catalog matching and replacement lookup

Detailed Description

Standard Ignition AC399 is an idle air control valve used to regulate bypass air at idle on supported BMW and Saab vehicles. When the original valve sticks, responds slowly, or no longer maintains stable idle speed, replacement can restore proper idle control and drivability. This part is listed for a wide range of BMW models including 325Ci, 330Ci, 330i, 330xi, X3, X5, 525i, 530i, Z3, and Z4, along with Saab 900 and 9-3 applications. This part cross-references Bosch 0280140545 for the same application.

What It Helps Fix

• Rough or unstable idle
• Idle speed that drops too low or stalls
• Idle flare or hanging idle after throttle release
• Air bypass control issues at closed throttle
• Check engine concerns related to idle air control performance

Installation Notes and Tips

Verify connector style, hose routing, and engine application before installation. Confirm the vehicle uses 2 hose connections and 3 blade terminals, and match the part to the exact BMW or Saab model year listed in fitment. Clean surrounding intake passages and inspect vacuum hoses, throttle body condition, and electrical connectors during service. Fits 2001-2006 BMW 330Ci, N/A. Fits 2004-2006 BMW X3, N/A. Fits 1996-1998 Saab 900, N/A.

Quality Assurance

Standard Ignition AC399 is cataloged as a replacement idle air control valve for the listed applications and is supported by interchange references for fitment verification during parts lookup.