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Turbo Models

  1. Check all connectors, hoses and routings for cracks, leakage, or restrictions and repair as needed. Bring engine to normal operating temperature and run at idle. Remove and plug vacuum hose at EGR control valve. If engine runs rough test EGR control valve.
  2. Remove plug from vacuum hose and connect vacuum gauge. With engine at idle, vacuum should not be present. Increase engine speed to 2500 RPM. Vacuum should be present. If procedure fails, test duty solenoid valve and EGI control unit terminals 2M and 2N.
  3. Install vacuum gauge between duty solenoid valve and EGR control valve. Increase engine speed to 2000 RPM and note amount of vacuum. Disconnect and plug vacuum hose at EGR control valve. Increase engine speed to 2000 RPM. Vacuum should be greater than previous reading. If procedure fails, test EGR position sensor, EGR duty solenoid valve and EGI control unit terminal 2F.
  4. With vacuum hose disconnected at EGR control valve and vacuum gauge connected, disconnect Green/Black wire of water temperature switch. Increase engine speed to 2500 RPM and ensure vacuum is not present. If vacuum is present, test duty solenoid valve and EGI control unit terminal 1H.
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