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Home >> Acura >> 1995 >> 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. Retrieve codes. If Code 21 does not appear, problem is intermittent. Inspect for poor connections at Variable Valve Timing and Lift Electronic Control System (VTEC) solenoid valve and ECM connector.
  2. If Code 21 exists, turn ignition off. Unplug VTEC solenoid valve 1-pin connector. Measure resistance between connector terminal and ground. If resistance is not 14-30 ohms, replace VTEC solenoid valve. If resistance is 14-30 ohms, connect ECM Test Harness (07LAJ-PT3010A ) between ECM and ECM harness. See Figure .
  3. Test for continuity between VTEC solenoid valve connector and test terminal A4. If continuity does not exist, repair open in wire between VTEC solenoid valve and ECM connector. If continuity exists, test for continuity between VTEC solenoid valve connector terminal and body ground.
  4. If continuity exists, repair short in wire between VTEC solenoid valve and ECM connector. If continuity does not exist, temporarily substitute known good ECM, then retest system.
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