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Test NTC-13A - Checking EGR System

WARNING: This page is about a different car, the 1995 Plymouth Voyager, 1995 Plymouth Grand Voyager, 1995 Dodge Grand Caravan, 1995 Dodge Caravan, and 1995 Chrysler Town & Country. However, it is still accessible from the selected car via links, so may be relevant.
  1. Disconnect vacuum hose from EGR solenoid. Connect vacuum gauge to disconnected vacuum hose. Start engine. If vacuum is more than 10 in. Hg at idle, go to step 3).
  2. If vacuum is less than 10 in. Hg at idle, disconnect EGR vacuum signal hose at intake manifold. Connect a vacuum gauge to intake nipple. Read vacuum gauge at idle. If vacuum is more than 10 in. Hg at idle, repair restriction or leak in vacuum hose to EGR solenoid. Perform TEST VER-2. If vacuum is less than 10 in. Hg at idle, repair plugged vacuum nipple at intake manifold. Perform TEST VER-2.
  3. Disconnect vacuum gauge. Reconnect vacuum hose to EGR solenoid. Disconnect vacuum hose from EGR valve. Connect vacuum gauge to disconnected hose. While observing vacuum gauge, disconnect EGR solenoid 2-way connector. If vacuum gauge did not read more than one in. Hg at any time, replace EGR valve assembly. Perform TEST VER-2.
  4. If vacuum gauge read more than one in. Hg at any time, disconnect hose to EGR valve backpressure signal tube. Turn ignition off. Adjust a shop air hose to 20 psi (1.4 kg/cm2 ). Connect shop air to nipple on base of EGR valve. Listen for a tone change while opening and closing throttle.
  5. If tone changes, replace EGR valve. Perform TEST VER-2. If tone does not change, remove vacuum gauge. Cap open nipple at EGR valve base. Connect hand vacuum pump to EGR valve.
  6. Start engine. Listen for engine RPM change while slowly applying vacuum to EGR valve. If engine RPM does not change, replace EGR valve. Perform TEST VER-2. If engine RPM changes, turn ignition off. Apply 10 in. Hg and hold for 30 seconds. If vacuum holds for 30 seconds, EGR system is functioning properly. Test is complete. If vacuum does not hold for 30 seconds, replace EGR valve. Perform TEST VER-2.
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