Chart C-7 Exhaust Gas Recirculation (EGR) System Check

EGR Diagnosis:

DFI Emission Circuit:

TEST DESCRIPTION: The numbers below refer to circled numbers on the diagnostic chart.

1. Checking for EGR valve's ability to flow sufficient exhaust gas to engine. Engine speed should drop and idle should become rough or stall. Compare the RPM drop to a known good car.

2. Checking for blocked EGR passages in the intake manifold.

3. Checking for EGR solenoid able to pass vacuum.

4. Checking for voltage to EGR solenoid and ground signal from the ECM. If either of these are missing, the EGR solenoid will command EGR on at all times.

5. Checking for ECM ability to turn solenoid off. If the light goes off, the electrical portion of the EGR system is OK.