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Makes 🢒 Cadillac 🢒 2003 🢒 CTS 🢒 Bulletins 🢒 Intermittent Stall Surge Stumble Or Hesitation DTC P1629 - keywords emulator gauge hesitation intermittent interrupt IPC message reset stall starter stumble surge swep

Intermittent Stall Surge Stumble Or Hesitation DTC P1629 - keywords emulator gauge hesitation intermittent interrupt IPC message reset stall starter stumble surge swep

Subject:Intermittent Stall, Surge, Stumble, or Hesitation DTC P1629

Models:2003 Cadillac CTS with 3.2L (LA3) Engine


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

Condition/Concern:

Some On rare occassions, customers may comment the engine will stall intermittently. The concern may also be described as a surge feel (not an accelerator surge), stumble, or hesitation while driving. Careful questioning of the customer, and the Diagnostic System Check, may reveal the following clues:

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The engine stalled at a steady state cruise speed with no driver inputs.

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In all reported cases, the vehicle has restarted.

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The condition is very intermittent and can take 100 miles or more to duplicate.

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The Instrument Panel Cluster (IPC) may reset and the gauges may sweep during or after the stall.

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The Driver Information Center (DIC) may display a starter interrupt message.

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DTC P1629 Theft Deterrent Fuel Enable Signal Not Received, may be stored in the Engine Control Module (ECM).

Note: The transmission can effectively push start the vehicle after the stall occurs at speeds as low as 35 mph. This would give the customer the perception the vehicle stalled and re-started on its own.

Important: This concern will NOT occur when the Tech 2 or Vehicle Data Recorder (VDR) is attached to the vehicle.

Recommendation/Instructions:

The concern may be the result of electrical noise on the Keyword 2000 Data Line (circuit 5043) that causes the ECM to reset. Install a Module Emulator Kit (Part Number 10357869). It will reduce the amount and amplitude of the noise on the circuit.

Components Provided in Kit:

Jumper (Require 1 Per Vehicle)

Terminal Part Number 12129484 (Require 2 Per Vehicle)

Tools Needed:

Crimping Tool

Wire Cutters

Wire Strippers

Soldering Iron

Pick To Remove Terminals

Black Vinyl Tape

Procedure:

  1. Locate ALDL Connector.
  2. Locate and Remove Pin 7 From ALDL Housing (Pin 7 Has CKT 5043, WH/BK, Which Is The K-Line.
  3. Cut Terminal Off Wire As Close To Terminal As Possible.
  4. Strip Small Portion Of Insulation Off Circuit 5043 and 5043A (One End Of PK Wire In Jumper assembly).
  5. Twist Wires Together and Double Crimp CKTS 5043 and 5043A With Terminal Part # 12129484.
  6. Solder Crimp.
  7. Locate and Remove Pin 5 from ALDL Housing (Pin 5 Has CKT 351E, BK/WH, Which Is Ground).
  8. Cut Terminal Off Wire As Close To Terminal As Possible.
  9. Strip Small Portion Of Insulation Off 351E and 5043B (Other End of PK Wire In Jumper assembly).
  10. Twist Wires Together And Double Crimp CKTS 351E and 5043B With Terminal Part # 12129484.
  11. Solder Crimp.
  12. Locate Best Spot To Package Jumper Assembly. (Tape Back To a Harness Bundle if Necessary /Possible Find Cubby Hole To Place it in, Whatever Works Best In Vehicle).

Important: Verify that the Tech 2 will communicate with the ECM and TCM after installation.

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.