P0401

Detection Condition:

Test Procedure:

Step 1 - 5:

Step 6 - 8:

DESCRIPTION
The Exhaust Gas Recirculation (EGR) system is designed to introduce exhaust gas into the combustion chamber. This lowers combustion temperatures and reduces the formation of oxides of nitrogen. The amount and timing of exhaust gas introduced into the combustion cycle varies by such factors as engine speed, engine vacuum, exhaust system back pressure, coolant temperature and throttle position.