2010 Cadillac CTS Sedan AWD V6-3.6L Page 982
P0088
The actual fuel rail pressure is 2 MPa (290 psi) greater than the desired fuel rail pressure. The condition exists for greater than 5 s.
P0089
The high pressure fuel pump actuator command necessary to maintain the desired fuel rail pressure is +/-2 MPa (290 psi) of the command expected
by the controller. The condition exists for greater than 5 s.
Action Taken When the DTC Sets
* DTCs P0087, P0088, and P0089 are Type A DTCs.
* A message center or an indicator displays Reduced Engine Power.
Conditions for Clearing the DTC
DTCs P0087, P0088, and P0089 are Type A DTCs.
Diagnostic Aids
* A condition with the fuel tank fuel pump module or fuel pump flow control module will set these DTCs.
* A skewed fuel rail pressure sensor, or an intermittent condition in the fuel rail pressure sensor circuits may set these DTCs.
* A leaking or restricted fuel injector may set DTC P0089.
Reference Information
Schematic Reference
Engine Controls Schematics (LLT) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)Engine Controls Schematics
(LF1) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Fuel System Description (See: Powertrain Management/Computers and Control Systems/Description and Operation/Fuel System Description)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit
Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Wiring Repairs/Wiring Repairs)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code
(DTC) Type Definitions)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Circuit/System Verification
1. Observe the DTC information with a scan tool. DTC P029D, P02A1, P02A5, P02A9, P02AD, P02B1, P0627, P0628, P0629, P069E, or
U0109 should not set.
瀚慖f a DTC is set refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code Descriptions/Diagnostic Trouble
Code (DTC) List - Vehicle).
2. Attempt to start and idle the engine.
3. Observe the DTC information with a scan tool. DTCs P0087, P0088, and P0089 should not set.
4. Engine idling, observe the Fuel Rail Pressure Sensor parameter with a scan tool. The pressure should be approximately 3.5-5.5 Mpa (508-798
psi).
5. Command an increase and decrease in fuel rail pressure with a scan tool. Observe the scan tool Fuel Rail Pressure Sensor parameter. The
Fuel Rail Pressure Sensor should increase or decrease with each commanded state.
6. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the
conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
