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EGR Function Testing Dodge Diplomat I

Testing & Diagnostics ~359 words

FLOOR JET

With engine off, remove air cleaner assembly. Open choke valve (if necessary) and throttle plate. Ensure floor jets are present and open.

NON-TURBO ENGINE

  1. Check vacuum lines for correct routing. Warm engine to operating temperature. Some models with EGR delay timers must run for at least 1-2 minutes before EGR works.
  2. While watching EGR pintle, abruptly accelerate engine to 2000-3000 RPM. EGR pintle should open at least 1/8".
  3. Connect a hand-held vacuum pump to EGR valve. Idle engine and gradually apply at least 10 in. Hg. EGR valve stem/diaphragm should move smoothly and engine speed should drop at least 150 RPM.

TURBO ENGINE

Check vacuum lines for correct routing. Disconnect vacuum hose at EGR valve. Warm engine to operating temperature. Connect a hand-held vacuum pump to EGR valve. With engine idling, slowly apply 2-3 in. Hg. Engine RPM should drop when vacuum is applied.

2.6L SUB-EGR CONTROL VALVE

  1. Check vacuum lines for correct routing. Disconnect Green-stripe vacuum hose from carburetor. Attach a hand-held vacuum pump to hose. With engine at idle speed, manually open sub-EGR control valve.
  2. Apply 6 in. Hg to EGR valve and ensure engine runs roughly. Reconnect vacuum hoses.

VACUUM AMPLIFIER

  1. Check for adequate manifold vacuum. With engine idling at normal operating temperature, connect a hand-held vacuum pump to hose on vacuum amplifier leading to venturi port on carburetor. Apply approximately 2 in. Hg.
  2. Disconnect hose to EGR delay timer (if equipped). EGR valve should open and engine speed should drop at least 150 RPM. If engine speed does not drop 150 RPM, replace vacuum amplifier.

EGR BACKPRESSURE TRANSDUCER (2.2L TURBO ONLY)

  1. Warm engine to operating temperature. Disconnect vacuum hose at backpressure transducer from EGR electronic control solenoid. Connect a vacuum gauge to hose.
  2. Increase engine speed to 2000 RPM. Vacuum gauge should read at least 5 in. Hg. Reconnect vacuum hose.
  3. Disconnect vacuum hose at EGR valve and connect hand-held vacuum gauge to hose. Repeat step 2). If further testing is required, see appropriate COMPONENT TESTING article in the EMISSION section.

ELECTRONIC EGR CONTROL SOLENOIDS

For electronic EGR control solenoid testing, see appropriate COMPONENT TESTING article in the EMISSION section.

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