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Code 17: Feedback System

  1. Perform after-repair procedure. See AFTER-REPAIR PROCEDURE  . If Code 17 is still present, go to next step. If Code 17 is not present, check O2S circuit for poor connection. Repair or replace connector as necessary. If connector is okay, perform CODE 15, OXYGEN SENSOR (O2S)  .
  2. Remove rear seat cushion. Disconnect fuel pump connector. Start and run engine until it stalls. Turn ignition off. Reconnect fuel pump connector and install rear seat cushion. Install fuel pressure gauge between fuel filter and main fuel line. Start engine and allow it to idle. With vacuum hose disconnected from fuel pressure regulator, fuel pressure should be 38-46 psi (2.7-3.2 kg/cm2 ). If fuel pressure is as specified, go to next step. If fuel pressure is low, go to step 5). If fuel pressure is high, check for a restricted fuel return hose. Repair or replace fuel line as necessary. If fuel return hose is okay, replace fuel pressure regulator.
  3. Check fuel injectors for leakage. Replace fuel injector(s) as necessary. If fuel injectors are okay, disconnect Engine Coolant Temperature (ECT) sensor and measure resistance between sensor terminals. If ECT sensor resistance is not as specified, replace ECT. If ECT sensor resistance is as specified, try a known good ECM and retest. See ENGINE COOLANT TEMPERATURE (ECT) SENSOR RESISTANCE  .
    ENGINE COOLANT TEMPERATURE (ECT) SENSOR RESISTANCE

    Temperature - °F (°C) Ohms
    176 (80) 317-325
    68 (20) 2200-2700
    -4 (-20) 14,600-17,800
  4. Disconnect each spark plug wire, one at a time, and check if engine speed decreases equally at each cylinder. If test results are okay, go to step 6). If test results are not okay, check for misfire of dead cylinder. Replace ignition components as necessary. If ignition components are okay, go to step 7).
  5. If fuel pressure is low in step 2), pinch off fuel return hose and check fuel pressure. If fuel pressure quickly increases, check fuel pressure regulator. Replace pressure regulator as necessary. If fuel pressure gradually increases, check for restriction between fuel pump and pressure regulator. Repair as necessary. If a restriction does not exist, check maximum fuel pump pressure. See the BASIC TESTING article in the ENGINE PERFORMANCE section. Replace fuel pump as necessary.
  6. Check air intake system for vacuum leaks. Repair as necessary. If no vacuum leaks exist, try a known good ECM and retest.
  7. Start engine and allow it to idle. Using a stethoscope, check for injector operating noise (clicking sound) at dead cylinder from step 4) inspection. If clicking noise is heard, go to next step. If no clicking noise is heard, check voltage at injector connector. If 12 volts is present, replace injector. If 12 volts is not present, check wiring harness for short or open circuit.
  8. Replace injector at dead cylinder. Perform after-repair procedure. See AFTER-REPAIR PROCEDURE  . If Code 17 is still present, try a known good ECM and retest. If Code 17 is not present, injector replacement corrected the problem.
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