lemon-mirror:
Home >> GMC >> 1975 >> Forward Control 4.8L Eng VIN T, Standard Trans >> Repair and Diagnosis >> Engine Performance >> Ignition System >> Transmission Controlled Spark System >> Operation >> Temperature Switch

Temperature Switch

Temperature switch provides a path to ground for cold override feature. When engine coolant temperature is below 93°F, vacuum is allowed to reach advance unit. When engine coolant temperature exceeds 93°F, temperature switch opens, returning vacuum advance to transmission gear position control.