ENGINE AND EMISSION CONTROL PARTS DESCRIPTION - Fuel Pump, Power Transistor & Ignition Coil, I.A.A. Unit, A.A.C. Valve

A turbine type design fuel pump is used and is situated in the fuel tank.

The ignition signal from the E.C.U. is amplified by the power transistor, which turns the ignition coil primary circuit on and off, inducing the proper high voltage in the secondary circuit. The ignition coil is a small, molded type. Both the power transistor and the ignition coil are integrated into the distributor assembly.

The I.A.A. unit is made up of the A.A.C. valve, F.I.C.D. solenoid valve and idle adjusting screw. It receives the signal from the E.C.U. and controls the idle speed at the preset value. The F.I.C.D. increases idle speed to compensate for power drain when the air conditioning compressor switches on. The F.I.C.D. is located on the throttle chamber, along with the Auxiliary Air Control (A.A.C.) valve.

The E.C.U. actuates the A.A.C. valve by an ON/OFF pulse. The longer that ON duty is left on, the larger the amount of air that will flow through the A.A.C. valve. The A.A.C. valve allows air to bypass the throttle valve to maintain optimum idle speed and compensate for load from the power steering and air conditioning.