Excessive Boost Pressure

1. From under vehicle, remove charging pressure regulator actuator line and connect handle held pressure pump.
2. Start engine and idle.
3. The inlet pipe to the pressure regulator should heat, while the bypass line remains cool.
4. Apply 8 - 14 psi (0.6 - 1.0 bar) to control valve.

Bypass line should heat

5. When applied pressure is suddenly removed, the valve should audibly click.
6. If valve did not function as specified, replace. End of test.
7. Remove timing valve and inspect check valve in center port for obstruction or binding.
8. Check pressure line to timing valve for damage or obstruction.
9. Repair as indicated.
10. Connect test light across disconnected timing valve electrical connection.
11. Turn ignition on.

Test light on, proceed to next step.
Test light off, system normal. End of test.

12. Check red/blue wire between K/CP and timing valve for short to ground. If OK, replace K/CP control unit.