How Do You Fix GM Nox Failure?
GM MPFI 3200, 3800, … engines failing NOX caused by lean condition. General Motors Multiport Fuel Injection engines may fail emissions standard testing due to excess Oxides of Nitrogen levels in the exhaust gas. Here are some steps to determine and correct the cause of high NOx emissions. • Understand that NOx is produced in the combustion chamber at temps higher than 2500F. The richer the air to fuel ratio (less than 14.7/1), the cooler the combustion will be, the leaner the air to fuel ratio (more oxygen), the hotter the combustion is and more NOx is produced. These particular engines either equipped or not with an EGR system may produce excessive NOx due to a lean condition. • Make sure that if equipped with a catalytic converter, it has not been removed. This device is located underneath the car in the exhaust system, between the exhaust manifold and the muffler. • Make sure the EGR (Exhaust Gas Recirculation/Recombustion) system is functioning properly, and particularly, that th
