P0401

DTC P0401 Exhaust Gas Recirculation (EGR) Sytem Malfunction








DESCRIPTION





The EGR valve is designed to lower peak combustion temperature and reduce oxides of nitrogen emissions (NOx) by recirculating exhaust gas through the intake manifold and the combustion chambers. It is not operated at idle and during engine warm up.

INSPECTION PROCEDURE

1. Turn the ignition switch to the OFF position. Inspect the EGR Solenoid Valve and connector terminals for looseness, poor contact, bending, corrosion, contamination, deterioration or damage.
2. Inspect EGR vacuum hoses for leaks, cracks, or kinked hose.
3. Measure the resistance between terminal 1 and 2 on the EGR Solenoid Valve.

Specifications (Resistance): 29.0 35.0 OHMS (at 20 degrees Celsius / 68 degrees Fahrenheit). If resistance is out of specifications, replace the EGR Solenoid Valve. If the EGR Solenoid Valve is good, continue Diagnostic Procedure.

Note:
Resistance may vary; depending on surrounding ambient temperature. If possible, compare readings with a known good solenoid.

SCHEMATIC DIAGRAM (EGR SYSTEM):

DIAGNOSTIC PROCEDURE: