KN3 - Check Vacuum Between Manifold Vacuum and FPRC Solenoid

- Key "OFF".

- Disconnect and inspect vacuum hose between the manifold vacuum source and the Fuel Pressure Regulator Control (FPRC) solenoid input vacuum port for blockage, kinks, cracks, etc.

- Is vacuum hose in good condition?

Yes -- Reconnect vacuum hose. Go to KN4. KN4 - Check Vacuum Signal Between FPRC Solenoid and Manifold

No -- Service or replace the vacuum hose as necessary. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)