Test FC-25A - EGR System Failure (DTC 32)
- Start engine. Allow engine to idle for at least 2 minutes. Disconnect vacuum supply hose from Exhaust Gas Recirculation (EGR) solenoid. Connect a vacuum gauge to end of disconnected hose. If vacuum gauge indicates less than 10 in. Hg, repair vacuum supply to EGR solenoid. Perform VERIFICATION PROCEDURE VER-2.
- If vacuum gauge indicates more than 10 in. Hg, reconnect vacuum hose to EGR solenoid. Disconnect vacuum hose from EGR valve. Connect a vacuum gauge to end of disconnected hose. While observing vacuum gauge, momentarily raise engine speed to more than 2000 RPM.
- If vacuum gauge indicated less than 5 in. Hg while throttle was opened, replace EGR valve assembly. Perform VERIFICATION PROCEDURE VER-2. If vacuum gauge indicated more than 5 in. Hg while throttle was opened, remove vacuum gauge.
- Connect a vacuum pump to EGR valve. With engine idling, slowly apply vacuum to EGR valve. If engine idle became rough as vacuum was applied, go to next step. If engine idle did not become rough, remove EGR valve and inspect manifold and EGR backpressure tube for restrictions. If restrictions are present, clean as necessary. Perform VERIFICATION PROCEDURE VER-2. If no restrictions are present, replace EGR valve assembly. Perform VERIFICATION PROCEDURE VER-2.
- Turn ignition off. Apply vacuum to EGR valve. Observe vacuum gauge. If vacuum was not held for at least 10 seconds, replace EGR valve assembly. Perform VERIFICATION PROCEDURE VER-2.
- If vacuum was held for at least 10 seconds, condition required to set fault is not present at this time. EGR SYSTEM FAILURE fault sets when Powertrain Control Module (PCM) performs a test of EGR system and monitors oxygen sensor signal for a change, but does not detect any change in oxygen sensor signal. Possible causes are: EGR valve not opening, EGR backpressure tube blocked or EGR passages in manifold blocked. Go to next step.
- Inspect all related vacuum hoses and connectors and repair as necessary. Perform VERIFICATION PROCEDURE VER-2. If no problems were found with vacuum hoses and connectors, see INACTIVE FAULT CONDITION . Perform VERIFICATION PROCEDURE VER-2.