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HOMESERVICE MANUALSCHEVROLET1985CAMARO Z28, 5.0 H, STANDARDREPAIR AND DIAGNOSIS (SINGLE PAGE)ENGINE PERFORMANCETESTING & DIAGNOSIS1.8L/2.5L TBI TESTS W/CODESCHART A6 - FUEL SYSTEM DIAGNOSIS
1985 Chevrolet Camaro Z28, 5.0 H, Standard

Chart A6 - Fuel System Diagnosis

1985 Chevrolet Camaro Z28, 5.0 H, StandardSECTION Chart A6 - Fuel System Diagnosis
NOTE: The following step numbers refer to the step numbers in the accompanying Flow Chart.
  1. 5) This step checks relay ground circuit No. 450.
  2. 6) This step checks ECM control of relay through circuit 465.
  3. 7) The fuel pump circuit includes an engine oil pressure switch. If fuel pump relay fails, the fuel pump will continue to run via oil pressure switch circuit. Relay failure will result in extended cranking times and possible no start condition.
  4. 8) This test checks the oil pressure switch to be sure it provides battery feed to fuel pump if pump relay fails.
  5. 9) This test checks for open oil pressure switch with ignition "OFF". Should switch stick closed, fuel pump will continue to run and discharge battery.
Fig 1: Chart A6 Schematic, Fuel System Diagnosis
G50E07640
RENDER: 1.0x

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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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