LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Dodge and Ram >> 1994 >> Caravan Base, 2.5 K, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests - 2.5L >> Emission Systems & Sub-Systems >> Exhaust Gas RECIRCULATION (EGR) >> EGR System Operation Check
April 5, 2026: LEMON Manuals is launched! Read the announcement.

EGR System Operation Check

  1. Warm engine to operating temperature. Attach a tachometer to engine. Run engine at idle in Neutral an additional 70 seconds.
  2. Accelerate engine speed abruptly to 2000-3000 RPM, and check EGR valve stem for movement. Repeat test to confirm stem movement, indicating EGR control system is functioning correctly. If EGR valve stem does not move, connect external vacuum source and recheck EGR valve stem for movement. If EGR operates normally on external vacuum source, go to step 6).
  3. If EGR valve stem does not move, check for cracked, leaking, disconnected or plugged vacuum hoses. Verify correct hose routing. Disconnect hose harness from EGR valve/transducer, and connect a vacuum pump to harness.
  4. Start engine, and raise engine speed to 2000 RPM and hold. Apply 10 in. Hg vacuum to EGR while checking for EGR valve movement. If no movement occurs, see TESTS W/CODES - 2.5L TBI article in the ENGINE PERFORMANCE section.
  5. If valve opens approximately 1/8" (3 mm), hold vacuum constant and check for valve diaphragm leakage. Valve should remain open for at least 30 seconds. If leakage occurs, replace valve/transducer assembly. If valve is okay, check control system.
  6. If EGR valve stem does not move in step 2) but operates normally on external vacuum source, remove throttle body and check port in throttle bore for blockage. Use a solvent to remove deposits, and check flow using light air pressure. Normal operation should be restored.
  7. If engine will not idle correctly or stalls, check for leaking EGR valve. With engine running, remove vacuum hose from EGR valve. If removing vacuum hose does not correct rough idle, remove EGR valve/transducer assembly. Check valve for proper seating. Replace assembly as necessary.
  8. Also check EGR-to-intake manifold tube for leak. Remove tube and inspect gasket. Tube end should be uniformly indented on gasket, without signs of leakage. If leakage is not evident, replace gaskets and tighten flange nuts to 17 ft. lbs. (23 N.m). If leak persists, replace EGR tube and gaskets.
NOTE: DO NOT use drills or wires to clean passages for EGR control system. Calibration of precision orifices could be altered, resulting in unsatisfactory vehicle operation.
scientia non olet · About LEMON Manuals