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Test NTC-14A - Checking EGR System

WARNING: This page is about a different car, the 1995 Dodge Ram Wagon, 1995 Dodge Ram Van, 1995 Dodge Pickup, and 1995 Dodge Dakota. However, it is still accessible from the selected car via links, so may be relevant.
  1. Disconnect Exhaust Gas Recirculation (EGR) solenoid vacuum supply hose. Connect a vacuum gauge to disconnected EGR vacuum supply hose. Start engine and operate at idle. If vacuum gauge indicates more than 10 in. Hg of vacuum at idle, go to step 3). If vacuum gauge does not indicate more than 10 in. Hg of vacuum at idle, disconnect EGR vacuum supply hose at intake manifold.
  2. Connect a vacuum gauge to intake manifold nipple. Operate engine at idle and read vacuum gauge. If vacuum gauge indicates more than 10 in. Hg of vacuum at idle, repair restriction or leak in vacuum supply hose between intake manifold and EGR solenoid. Perform TEST VER-2. If vacuum gauge does not indicate more than 10 in. Hg of vacuum at idle, repair plugged vacuum nipple at throttle body. Perform TEST VER-2.
  3. Disconnect vacuum gauge. Reconnect EGR solenoid vacuum supply hose. Disconnect EGR valve hose. Connect a vacuum gauge to disconnected EGR valve hose. Observe vacuum gauge and momentarily snap throttle open. If vacuum gauge does not indicate more than 5 in. Hg of vacuum with throttle open, replace EGR valve assembly. Perform TEST VER-2.
  4. If vacuum gauge indicates more than 5 in. Hg of vacuum with throttle open, disconnect EGR valve back pressure signal tube. Adjust shop air hose to 20 psi. Turn ignition off. Connect shop air hose to nipple on base of EGR valve. Listen for a tone change while opening and closing throttle. If tone changes, replace EGR valve assembly. Perform TEST VER-2.
  5. If tone does not change, remove vacuum gauge. Cap open nipple on base of EGR valve. Connect a hand vacuum pump to EGR valve. Start engine. Listen for a speed change while slowly applying vacuum to EGR valve. If engine speed does not change, replace EGR valve assembly. Perform TEST VER-2.
  6. If engine speed changes, turn ignition off. Apply 10 in. Hg of vacuum and hold for 30 seconds. If vacuum holds for 30 seconds, EGR system is okay. Test is complete. If vacuum does not hold for 30 seconds, replace EGR valve assembly. Perform TEST VER-2.
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