Patent ID: 9175623
Filing Date: 2015-11-03
Classification: B60W,F02D,G01F,G01M,Y02T

Abstract:
1. An internal combustion engine comprising: cylinders within which fuel combusts to operate the engine; an exhaust gas recirculation (EGR) system; an intake system comprising a first portion through which air for supporting fuel combustion enters and passes to a mixing point at which any exhaust which has been created by fuel combustion and is allowed to pass through the EGR system entrains with air which has passed through the first portion of the intake system to create a mixture which then passes through a second portion of the intake system to the cylinders; a mass airflow (MAF) sensor providing an output signal measuring mass flow of air which has entered and is passing through the first portion of the intake system: a controller for causing the EGR system to disallow passage of any exhaust to the mixing point and concurrently executing a strategy for evaluating calibration of the MAF sensor by operating the engine at each of different combinations of engine speed and engine load, and for each combination of engine speed and engine load, recording a corresponding output signal of the MAF sensor and also calculating mass flow passing through the second portion of the intake system as a function of pressure in the second portion of the intake system, temperature in the second portion of the intake system, speed of the engine, and volumetric efficiency of the engine; and using the output signal of the MAF sensor and the calculated mass flow passing through the second portion of the intake system at at least one combination of engine speed and engine load to evaluate the calibration the MAF sensor.