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Home >> Acura >> 1993 >> Integra GS-R >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Trouble Codes >> Code 43: Fuel Supply System
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Code 43: Fuel Supply System

  1. If referred here from CODE 1, go to step 2. If Code 43 exists, turn ignition off. Remove BACK-UP fuse (7.5-amp) from underhood fuse/relay box for 10 seconds to reset ECM. Warm engine until cooling fan comes on. With transmission in Neutral, raise engine speed to 3000 RPM and hold for 2 minutes. Check ECM for fault codes. If Code 43 does not exist, problem is intermittent. Check for poor connections at ECM, HO2S and wiring harness connectors.
  2. If Code 43 is present, turn ignition off. Connect ECM Test Harness (07LAJ-PT3010A ) between ECM and ECM connectors. See Figure . Wait 2 minutes. Install jumper wire between test terminals A6 and A26. Turn ignition on while measuring voltage between terminals D14 (+) and A26 (-).
  3. If 0.1 volt or less is present as ignition is turned on, go to step 5. If more than 0.1 volt is present as ignition is turned on, disconnect HO2S connector. Measure voltage between HO2S wiring harness connector Green/White and White wire terminals.
  4. If more than 0.1 volt is present, replace HO2S. If 0.1 volt or less is present, repair open circuit in Green/White or White wire between HO2S and ECM connector.
  5. If 0.1 volt or less was present as ignition was turned on in step 3, disconnect HO2S connector. Measure voltage between test terminals D14 (+) and A26 (-). If more than 0.1 volt is present, replace HO2S. If 0.1 volt or less is present, disconnect connector "D" from wiring harness. Measure voltage between test terminals D14 (+) and A26 (-). If more than 0.1 volt is present, repair short in White wire between ECM connector and HO2S. If 0.1 volt or less is present, replace ECM and retest.
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