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Test TC-24A - EGR System Failure (DTC 32)

WARNING: This page is about a different car, the 1995 Plymouth Voyager, 1995 Plymouth Grand Voyager, 1995 Dodge Grand Caravan, and 1995 Dodge Caravan. However, it is still accessible from the selected car via links, so may be relevant.
  1. Start engine. Allow engine to idle for 2 minutes. Disconnect EGR solenoid electrical connector. Leave EGR solenoid electrical connector disconnected for remainder of test. Disconnect vacuum supply hose to EGR solenoid. Connect a vacuum gauge to disconnected hose. If vacuum gauge reading is less than 10 in. Hg, repair vacuum supply hose to EGR solenoid. Perform TEST VER-2.
  2. If vacuum gauge reading is more than 10 in. Hg, reconnect vacuum hose to EGR solenoid. Disconnect vacuum hose from EGR valve. Connect a vacuum gauge to disconnected hose. While observing vacuum gauge, momentarily increase engine speed to more than 2000 RPM.
  3. If vacuum gauge reading is more than 5 in. Hg when throttle is opened, go to next step. If vacuum gauge reading is less than 5 in. Hg when throttle is opened, replace EGR valve assembly. Perform TEST VER-2.
  4. Remove vacuum gauge. Connect a vacuum pump to EGR valve nipple. With engine idling, slowly apply vacuum to EGR valve while observing engine idle speed. If engine idle is rough or stalls when vacuum is applied, go to step 6).
  5. If engine does not idle rough or stall when vacuum is applied, remove EGR valve and inspect manifold and tube for restrictions. Repair as required. Perform TEST VER-2. If no restrictions are found, replace EGR valve assembly. Perform TEST VER-2.
  6. Turn ignition off. Apply vacuum to EGR valve nipple. Observe vacuum gauge. If vacuum does not hold for at least 10 seconds, replace EGR valve assembly. Perform TEST VER-2. If vacuum holds for at least 10 seconds, go to next step.
  7. At this time, condition required to set DTC is not present. EGR SYSTEM FAILURE DTC occurs when Powertrain Control Module (PCM) performs a test of EGR system and monitors O2S signal for a change. PCM will repeat EGR system test up to 8 times in one run cycle. If test fails every time, PCM will set a DTC. If any of the tests pass, diagnostics are suspended for the run cycle. Possible causes are: open or blocked vacuum supply to EGR valve, blocked exhaust transfer tubes to intake manifold, blocked backpressure tube to transducer, failed EGR valve, failed EGR solenoid or transducer, or failed PCM. Go to next step.
  8. Inspect vacuum hoses and connectors. Repair as required. Perform TEST VER-2. If vacuum hoses and connections are okay, see INACTIVE DTC CONDITION  .
  9. Perform TEST VER-2.
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