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Makes 🢒 Cadillac 🢒 2005 🢒 XLR 🢒 Bulletins 🢒 SMU - Revised DTC P0171 or P0174

SMU - Revised DTC P0171 or P0174

Subject:Revised DTC P0171 or P0174

Models:2004-2005 Cadillac SRX, STS, XLR
with 4.6L V8 Engine (VIN A - RPO LH2)


This bulletin is being issued to revise Steps 2 and 3 of DTC P0171 or P0174 in the Engine Controls sub-section of the Service Manual. Please replace the current information in the Service Manual with the following information.

The following information has been updated within SI. If you are using a paper version of this Service Manual, please make a reference to this bulletin on the affected page.

Step

Action

Values

Yes

No

2

Important: If any DTCs other than P0171 or P0174 are set, refer to those DTCs before continuing.

  1. Install scan tool.
  2. Start and idle the engine at the normal operating temperature in Closed Loop.
  3. Record the short term and long term fuel trim data.
  4. Turn OFF the engine.
  5. Turn ON ignition, with the engine OFF.
  6. Review the Freeze Frame/Failure Records, and record the displayed data for this DTC.

Does the scan tool indicate that the combined value of the short term and the long term fuel trim is greater than the specified value?

25%

Go to Step 3

Go to Diagnostic Aids

3
  1. Operate engine at idle.
  2. Observe heated oxygen sensor (HO2S) bank 1 sensor 1 and bank 2 sensor 1 parameters with a scan tool.

Does the scan tool indicate that the lambda values are within the specified range?

0.96-1.04

Go to Step 4

Go to Step 5