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Home >> Acura >> 1994 >> Integra GS-R, 2D Coupe >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Trouble Codes >> Code 21: VTEC Solenoid Valve (1.8L GS-R)
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Code 21: VTEC Solenoid Valve (1.8L GS-R)

  1. 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. Road test vehicle. While in 1st gear, accelerate until engine speed reaches 6000 RPM and hold for at least 2 seconds. Repeat procedure 3 times. Check ECM for fault codes. If Code 21 is not present, problem is intermittent. Check for poor connections at Variable Valve Timing and Lift Electronic Control System (VTEC) solenoid valve and ECM connector.
  2. If Code 21 is present, turn ignition off. Disconnect VTEC solenoid valve 1-pin connector. Check resistance between connector terminal and body ground. If resistance is not 14-30 ohms, replace VTEC solenoid valve. If 14-30 ohms are present, connect ECM Test Harness (07LAJ-PT3010A ) between ECM and ECM connectors. See Figure.
  3. Check for continuity between VTEC solenoid valve connector and test terminal A4. If continuity is not present, repair open in wire between VTEC solenoid valve and ECM connector. If continuity is present, check for continuity between VTEC solenoid valve connector terminal and body ground.
  4. If continuity is present, repair short in wire between VTEC solenoid valve and ECM connector. If continuity is not present, replace ECM and retest.
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