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Home >> Buick >> 1996 >> Roadmaster Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control Systems - Tests W/Codes >> Diagnostic Trouble Codes >> DTC P1171 - Fuel System Lean During Acceleration >> Diagnostic Procedures
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Diagnostic Procedures

  1. Perform On-Board Diagnostic (OBD) System Check. After performing OBD system check, go to next step.
    NOTE: If any HO2S related DTC is present, diagnose affected code first.
  2. Turn ignition off. Install fuel pressure gauge. Turn ignition on, with engine off. Fuel pump should operate for about 2 seconds. It may be necessary to cycle ignition on more than once to obtain maximum fuel pressure reading. Note fuel pressure with fuel pump running. Fuel pressure should be 41-47 psi (2.9-3.3 kg/cm2 ) and hold steady. If fuel pressure is as specified, go to next step. If fuel pressure is not as specified, diagnose fuel system. See SYSTEM/COMPONENT TESTS article.
  3. Check for restricted fuel filter, restricted or damaged fuel line, restricted/clogged fuel pump strainer. Repair as necessary. After repairs, go to step 5). If components are okay, go to next step.
  4. Replace fuel pump. After replacing fuel pump, go to next step.
  5. Using scan tool, select DTC, CLEAR INFO. Start and warm engine to normal operating temperature. Select DTC, SPECIFIC, then enter DTC P1171. Operate vehicle within the conditions for setting this DTC. If scan tool indicates that this test ran and passed, go to next step. If scan tool does not indicate that this test ran and passed, repeat step 2).
  6. Using scan tool, select CAPTURE INFO, REVIEW INFO function. If any undiagnosed DTC(s) are displayed, go to applicable DTC test.
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