LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Chevrolet >> 1998 >> Prizm Base, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Circuit Tests >> Fuel Injector Circuit >> Diagnosis & Repair
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnosis & Repair

  1. Perform On-Board Diagnostic (OBD) system check. See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK under SELF-DIAGNOSTIC SYSTEM in TESTS W/CODES article. After performing OBD system check, go to next step.
  2. Check for clean and tight PCM ground connections. Check for faulty IGN fuse or EFI fuse. Check quality of fuel. If a problem is found, go to next step. If connections, fuses or fuel quality is okay, go to step 4).
  3. Repair problem as necessary. After repairs, go to step 17).
  4. Turn ignition off. Install Fuel Pressure Gauge (J-34730-1A). Turn ignition on with engine off. Fuel pump should run for about 3 seconds. Cycle ignition on and off several times to establish an accurate reading. Fuel pressure reading should be 44-50 psi (3.0-3.4 kg/cm2 ). If fuel pressure is as specified, go to next step. If fuel pressure is not as specified, check fuel system electrical circuit. See FUEL SYSTEM ELECTRICAL CIRCUIT under NO START - ENGINE CRANKS OKAY under NO START DIAGNOSIS in BASIC TESTING article.
  5. Turn ignition off. Remove fuel pressure gauge. Disconnect all 4 fuel injector electrical connectors. Install Fuel Injector Test Light (J-34730-2B) on each fuel injector harness connector. Crank engine and observe test light for each injector. If test light flashes for each injector while cranking engine, go to next step. If test light does not flash for each injector, go to step 8).
  6. Perform Fuel Injector Coil Test - Engine Coolant Temperature Between 50-95°F. See FUEL INJECTOR COIL TEST - ENGINE COOLANT TEMPERATURE BETWEEN 50-95°F. Replace any fuel injector(s) as necessary. After repairs, go to step 17). If fuel injector(s) is okay, go to next step.
  7. Check fuel for contamination. If fuel is contaminated, clean fuel system and repair cause for contamination. After repairs, go to step 17). If fuel is okay, go to step 16).
  8. If test light remains illuminated on any injector while cranking engine, go to next step. If test light does not remain illuminated on any injector, go to step 10).
  9. Check for an short to ground in fuel injector control circuit between fuel injector and PCM. Repair as necessary. After repairs, go to step 17). If circuit is okay, go to step 15).
  10. Remove test light from fuel injector harness connector. Turn ignition on with engine off. Using a test light connected to ground, probe fuel injector connector (harness side) ignition feed circuit. See WIRING DIAGRAMS article. Repeat on injectors that are inoperative. If test light illuminates, go to next step. If test light does not illuminate, go to step 12).
  11. Using a test light connected to battery voltage, probe fuel injector connector (harness side) fuel injector control circuit. See WIRING DIAGRAMS article. Crank engine and observe test light. Repeat on injectors that are inoperative. If test light flashes, go to DIAGNOSTIC AIDS. If test light does not flash, go to step 13).
  12. Check for an open or short in ignition feed circuit between fuel injector and ignition switch. Repair as necessary. After repairs, go to step 17). If circuit is okay, go to step 14).
  13. Check for an open or short in fuel injector control circuit between fuel injector and PCM. Repair as necessary. After repairs, go to step 17). If circuit is okay, go to step 15).
  14. Replace ignition switch. After repairs, go to step 17).
  15. Replace PCM. After repairs, go to step 17).
  16. Check for engine mechanical problem. Check for incorrect valve timing, faulty or incorrect camshaft, leaking or sticky valves or rings, excessive valve deposits, loose or worn rocker arms, weak valve springs, or leaking head gasket. After repairs, go to next step. If no problems are found, go to DIAGNOSTIC AIDS.
  17. Using scan tool, clear Diagnostic Trouble Codes (DTCs). Attempt to start engine. If engine starts and continues to run, go to next step. If engine does not start, or starts and stalls, go to step 2).
  18. Warm engine to normal operating temperature. Check for DTC(s). If DTC(s) is present, diagnose DTC(s). See TESTS W/CODES article. If DTC(s) is not present, system is okay.
scientia non olet · About LEMON Manuals