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Home >> Suzuki >> 2002 >> Grand Vitara JLS, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0171 Or DTC P0172 >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

  1. Check for DTCs P0131, P0132, P0133 and P0134. See RETRIEVING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. If DTCs are not set, go to next step. If any DTC is set, go to that test first.
  2. Perform DTC CONFIRMATION TEST  . If DTC P0171 or P0172 is set, go to next step. If DTCs P0171 and P0172 are not set, problem is intermittent. System is okay at this time. See INTERMITTENTS TROUBLE SHOOTING - NO CODES article.
  3. If other DTCs are set, go to that test first. Check intake and exhaust system for leakage. Repair as necessary and go to DTC CONFIRMATION TEST  . If intake and exhaust system are okay, go to next step.
  4. Perform fuel pressure test. See FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary and go to DTC CONFIRMATION TEST  . If fuel pressure is okay, go to next step.
  5. Check fuel injector resistance on cylinders No. 1, 3 and 5. See INJECTOR RESISTANCE in SERVICE & ADJUSTMENT SPECIFICATIONS article. Replace injector(s) as necessary. If fuel injector resistance is okay, go to next step.
  6. Check fuel injector circuit operation. See B-1: FUEL INJECTOR CIRCUIT INSPECTION in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary and go to DTC CONFIRMATION TEST  . If fuel injector circuit is okay, go to next step.
  7. Check fuel level sensor operation. See ENGINE SENSORS & SWITCHES in SYSTEM & COMPONENT TESTING article. Repair as necessary and go to DTC CONFIRMATION TEST  . If fuel level sensor is okay, go to next step.
  8. Check MAF sensor operation. See ENGINE SENSORS & SWITCHES in SYSTEM & COMPONENT TESTING article. Repair as necessary and go to DTC CONFIRMATION TEST  . If MAF sensor is okay, go to next step.
  9. Check ECT sensor operation. See ENGINE SENSORS & SWITCHES in SYSTEM & COMPONENT TESTING article. Repair as necessary and go to DTC CONFIRMATION TEST  . If ECT sensor circuit is okay, go to next step.
  10. Check HO2S Bank 1, Sensor 1 operation. See DTC P0134: HO2S BANK NO. 1 (LEFT BANK), SENSOR NO. 1 (BANK 1, SENSOR 1) CIRCUIT, NO ACTIVITY DETECTED  . Replace as necessary and go to DTC CONFIRMATION TEST  . If HO2S Bank 1, Sensor 1 is okay, replace ECM (PCM) and go to DTC CONFIRMATION TEST  .
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