초록

An EGR system monitor combines an inferred manifold absolute pressure based on measured mass air flow with a measured manifold absolute pressure to obtain a more complete system response during a test procedure involving the opening and closing of the EGR valve.

대표청구항 ▼

[ What is claimed is:] [1.]1. A method of monitoring the integrity of an EGR system of an automotive engine having an intake manifold and an exhaust manifold interconnected by an EGR line for recirculating exhaust gas to said intake manifold through an EGR valve located in said EGR line, comprising

[ What is claimed is:] [1.]1. A method of monitoring the integrity of an EGR system of an automotive engine having an intake manifold and an exhaust manifold interconnected by an EGR line for recirculating exhaust gas to said intake manifold through an EGR valve located in said EGR line, comprising a sequence of the following steps:determining first pressure values based on measured manifold absolute pressure and inferred manifold absolute pressure when said EGR valve is open;determining second pressure values based on measured manifold absolute pressure and inferred manifold absolute pressure when said EGR valve is closed;determining a difference pressure value based on the difference between said first and second pressure values;making a decision on the integrity of the EGR system based on said difference pressure value.