Checking Function

1984 Volkswagen Jetta GL, 1.6 HSECTION Checking Function
  1. Engine oil temperature 50°C (122°F) minimum.
  2. Start engine and let idle.

    EGR valve diaphragm rod is pulled toward vacuum hose connector.

    Diaphragm rod visible through opening on back side of diaphragm means exhaust gas is being supplied.

  3. Slowly increase engine speed, when engine speed exceeds 1200 RPM, EGR is interrupted for 2 seconds.

    Diaphragm rod moves toward intake manifold for 2 seconds then moves back toward vacuum connection.

  4. Continue to raise engine speed until part throttle switch closes.

    Diaphragm rod moves back toward intake manifold means EGR is interrupted.

If EGR does not work as described, go to Checking Activation .

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.