Vacuum Routing Diagrams — Ford Bronco 1987-1991
Technical Reference
Member-uploaded diagrams & documents for this generation. AI-classified; community-verified where badged.
Vacuum Routing
- Secondary air injection combination/bypass valve showing inlet from air pump, vacuum port S (air control), port D (air bypass), outlet B to catalyst and outlet A to engine.
- Underhood emissions/vehicle information label showing vacuum hose routing diagram, spark plug gap and timing specs.
- Emissions vacuum routing diagram showing color-coded hoses connecting the carbon canister, EGR, EVR, MAP, FPRC, solenoid valves and throttle body.