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Home >> Acura >> 1988 >> Integra SE, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Electronic Control System >> Testing Information >> Code 1 &/Or Code 2 - Oxygen Sensor
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Code 1 &/Or Code 2 - Oxygen Sensor

  1. Turn off ignition and reset ECU. Remove hazard fuse at battery terminal for 10 seconds. Start engine. Check fuel pressure at fuel filter. See appropriate FUEL INJECTION article. Repair fuel system if not within specifications. If fuel pressure is within specifications, proceed to next step.
  2. Bring engine to operating temperature (cooling fan on). Hold engine at 1500 RPM for 15 minutes, without closing throttle completely during this time. Check if PGM-FI or Check Engine warning light is on. If not on, problem is intermittent. Test drive and check light again.
  3. If light is on, disconnect indicated oxygen sensor connector. Attach voltmeter to vehicle ground and connector. With engine at normal operating temperature, momentarily open throttle wide open, then close throttle.
  4. Voltage at wide open throttle should be greater than .6 volt, and less than .4 volt at full closed throttle. If not within specifications, replace oxygen sensor. If voltage is within specifications, proceed to next step.
  5. Turn engine off and attach system checker harness between ECU and ECU connector. Using a voltmeter, connect negative terminal to connector terminal A18.
  6. Attach positive voltmeter lead to connector terminal C16.
  7. Start engine and warm to operating temperature. Momentarily open throttle wide open, then close throttle. Voltage at wide open throttle should be greater than .6 volt and less than .4 volt at full closed throttle. If not within specification, repair wire between ECU and oxygen sensor. If within specification, substitute a known good ECU. If condition is rectified, replace original ECU.
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