Pressure Control Retard Mechanism (Turbo)
- Pressure retard control mechanism prevents engine knock when turbocharger is in operation. A defective pressure control system may result in reduced turbocharging pressure. Test system as follows.
- Disconnect distributor vacuum hose from throttle housing. Connect hand-held Pressure Pump (83 93 514 ) and install pressure gauge in vacuum hose to distributor. Start and run engine at idle speed. Check ignition timing. Apply 7.2 psi (.50 Kg/cm2 ) pressure to distributor diaphragm. Ensure ignition timing retards 3-7 degrees.