Intermittent No Power MIL With TPS TAC TCM DTCs Set - keywords PIINSI 3.2L acceleration check connector contamination display driveability DTC ECM engine hard harness hesitate hesitation idle

This PI was superseded to update part numbers. Please discard PIP3370.

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Concern on the 2003 Cadillac CTS of a lack of power, stalls or when pressing down on the accelerator pedal the vehicle will not accelerate. This condition can be intermittent or have the MIL "On" with ECM, TPS, TCM and TAC DTCs with a reduction in engine power message displayed on the IPC.

The diagnostics may lead you to replace the TPS which is part of the throttle body assembly. The concern may not be with the throttle body assembly. The concern may be with the engine harness connector and terminals to the throttle body assembly. Before replacement of the throttle body assembly, check the engine harness connector and wire terminals to the throttle body assembly and replace as necessary. Refer to SI Document ID # 303631, testing for intermittent and poor connections and SI Document # 303628, for testing for electrical intermittent.

Engine harness connector pigtail part numbers GM 15306420 or Saturn 15318094 are available. Engine harness connector terminal part number (six are needed) 9628855 are also available and can be located in electrical terminal kit (Yazaki Tray 15 position 13). Use self-sealing connectors to make the connection and do not solder the wires. Refer to SI Document ID # 303648, splicing copper wire using splice sleeves.

Throttle body assembly part number 09128412. Refer to SI Document ID # 799178, throttle body assembly replacement and SI document number 799179, for throttle body service.

Note: GM dealers must call a Saturn dealer to order part number 15318094, if the GM part number 15306420 is not available.

For additional information on the TAC system, refer to SI Document ID # 820892, for TAC system description of operation.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.