Line Pressure Too High
- Vacuum system leak or improper engine vacuum. Water in vacuum modulator. Modulator valve not operating properly or defective. Defective EGR valve.
- Detent switch actuated or shorted, detent solenoid stuck open. Detent feed orifice in spacer plate blocked, detent solenoid loose. Detent valve bore plug damaged. Detent regulator valve pin too short.
- Pump pressure regulator and/or boost valve stuck. Incorrect pump pressure regulator spring. Pressure boost valve installed backward. Too many pressure regulator valve spacers. Pump casting defective. Aluminum bore plug has hole or not working. Pressure boost bushing broken or not working.
- Control valve assembly-to-spacer gasket out of proportion, control valve assembly gaskets switched.