Turbo Pressure Switch

Two positive pressure switches, which are combinations of a pressure withstanding diaphragm and microswitch, are mounted in front of the body strut mount. One switch operates when the intake manifold pressure reaches 1.97 in. Hg. This causes the turbo indicator lamp to illuminate, indicating that the turbocharger has begun its supercharging operation.

At the same time, it also transmits the heavy load signal to the MPFI control box for cancelling the air/fuel ratio feedback control. The other switch operates at a pressure of 18.50 in. Hg for cutting off fuel when an abnormal rise in supercharging pressure occurs, due to a failed turbocharger wastegate or other fault, thereby preventing damage to the engine.