Engine Controls - System & Component Testing - Except Coupe: Diagnosis Chrysler LHS II

EGR Flow Test (Except Concorde, Intrepid, LHS & 300M)

Note. Use the following test to determine if exhaust gas is flowing through EGR valve and EGR passages.

1. Disconnect vacuum hose from EGR valve. Connect a hand vacuum pump to EGR valve. Start engine. Apply 5 in. Hg of vacuum to EGR valve. Idle speed should drop or engine should stall. If idle speed does not drop, remove EGR valve from engine.
2. Apply vacuum to EGR valve. If EGR valve stem moves, valve is okay. Go to next step. If EGR valve stem does not move, replace EGR valve and transducer assembly.
3. Remove EGR tube from intake and exhaust manifolds. Clean EGR tube and related openings in manifolds. DO NOT attempt to clean EGR valve. Replace EGR valve if it is plugged with carbon.

EGR Valve Leakage Test (Except Concorde, Intrepid, LHS & 300M)

Note. Use the following test to determine if EGR valve is leaking in the closed position.

1. Turn engine off. Disconnect vacuum hose from EGR valve. Connect a hand vacuum pump to EGR valve. Apply 15 in. Hg of vacuum to EGR valve. Observe vacuum gauge on vacuum pump. If vacuum gauge drops, replace EGR valve and transducer assembly.
2. Disconnect EGR transducer backpressure hose from EGR valve. Remove air cleaner housing from throttle body. Apply about 50 psi of compressed air to backpressure hose fitting on EGR valve. Open throttle to WOT position.
3. Air should not be heard entering intake manifold. If air is heard entering intake manifold, EGR valve is leaking. Replace EGR valve and transducer assembly. DO NOT attempt to clean EGR valve.

EGR Transducer Electrical Test (All Models)

For electrical testing of EGR transducer, see DTC P0403: EGR SOLENOID CIRCUIT test in appropriate SELF-DIAGNOSTICS article.

EGR Transducer Vacuum Test (Except Concorde, Intrepid, LHS & 300M)

1. Disconnect backpressure hose from EGR valve. Connect a hand vacuum pump to backpressure hose fitting on EGR valve. Apply 10 in. Hg of vacuum to fitting. If vacuum does not hold, replace EGR valve and transducer assembly.
2. If vacuum holds, reconnect backpressure hose. Disconnect vacuum supply hose from EGR transducer solenoid. Connect a vacuum gauge to disconnected hose. Start engine and bring to normal operating temperature. Hold engine speed at 1500 RPM.
3. Full manifold vacuum should exist. If full manifold vacuum does not exist, repair vacuum hose to engine. If full manifold vacuum exists, turn engine off. Reconnect vacuum hose. Disconnect vacuum outlet hose from EGR transducer solenoid. Connect a vacuum gauge to fitting. Hold engine speed at 2000 RPM.
4. With the aid of an assistant, temporarily increase exhaust system backpressure while observing vacuum gauge. Full manifold vacuum should exist. When backpressure is released, vacuum gauge reading should be low. If vacuum is not as specified, replace EGR valve and transducer assembly.