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Home >> Dodge and Ram >> 1999 >> Caravan Base, 2.4 B >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System & Component Testing >> Emission Systems & Subsystems >> Exhaust Gas RECIRCULATION (EGR) System >> EGR Valve Gas Flow Test
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EGR Valve Gas Flow Test

  1. Test may be used to determine if exhaust gas is flowing through EGR valve, EGR tube, intake manifold and exhaust manifold. Start engine and warm engine to normal operating temperature. Shut engine off.
  2. Note location of hoses on EGR valve and EGR backpressure transducer. See Figure . Hose at top of EGR valve supplies vacuum to EGR valve. Hose on signal tube at bottom of EGR valve supplies exhaust pressure to EGR backpressure transducer.
  3. Disconnect hose from top of EGR valve. Start engine and allow engine to idle. Using vacuum pump, slowly apply 5 in. Hg of vacuum on hose fitting at top of EGR valve and note engine operation. With vacuum applied, engine idle speed should decrease and/or engine may stall to indicate exhaust gas is flowing through EGR tube between intake manifold and exhaust manifold.
  4. If engine idle speed decreases and/or engine stalls, go to step  7 . If engine idle speed does not decrease and/or engine stalls, this indicates exhaust gas is not flowing through EGR system. Shut engine off.
  5. Remove EGR valve. Using vacuum pump, slowly apply vacuum on hose fitting at top of EGR valve while noting movement of poppet valve on EGR valve. If poppet valve moves with vacuum applied, EGR valve is operating properly. Go to next step. If poppet valve does not move with vacuum applied, replace EGR valve and recheck system operation.
  6. Remove EGR tube located between intake manifold and exhaust manifold. Check EGR tube and passages in intake manifold and exhaust manifold for restrictions caused by excessive carbon deposits. Clean EGR tube and passages as necessary. Also check base of EGR valve for excessive carbon deposits. DO NOT attempt to clean EGR valve. If excessive carbon deposits exist at base of EGR valve, replace EGR valve. Reinstall components and recheck system operation.
  7. Shut engine off. Remove vacuum pump. Reinstall hose at top of EGR valve.
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