Idle Air Control Valve (IAC)

This category on the website [ Servos Valves and Wiring ] we are giving you all of the information related to the individual parts in the Buick Turbo Regal, along with the associated wiring, connector plugs, etc.

VEHICLE APPLICATION:

Buick Regal, T-Type, Turbo T, Limited, Grand National, GNX

VALVE NAME:

Idle Air Control Valve (IAC)

PURPOSE OF VALVE:

controls the air flow at idle

TURNS ON-OFF / FUNCTIONS / USED WHEN:

in constant use when the engine is running

LOCATION IN VEHICLE:

engine compartment, front of motor, underneath up pipe, front side of throttle body

ORIGINAL GM PART NUMBER:

25527077

VALVE BASE COLOR:

black
replacements are (silver colored) metal

CONNECTOR PLUG COLOR (VALVE SIDE):

black

WIRES ATTACHED (VALVE SIDE):

n/a

CONNECTOR PLUG COLOR (HARNESS SIDE):

black

NUMBER OF WIRES ATTACHED (HARNESS SIDE):

COLOR & PURPOSE OF (HARNESS SIDE) WIRES:

blue-white “A”, goes to ECM (“C5” coil A high)
blue-black “B”, goes to ECM (“C6” coil A low)
light green-white “C”, goes to ECM (“C4” coil B high)
light green-black “D”, goes to ECM (“C3” coil B low)

OTHER NOTES:

this is actually an electric motor.

some people use a custom angled adapter plate to mount the IAC valve in (this offsets the motor 45 degrees for better up pipe clearance).