| US 7,367,188 B2 | ||
| System and method for diagnostic of low pressure exhaust gas recirculation system and adapting of measurement devices | ||
| David Barbe, Ann Arbor, Mich. (US); Michiel J. van Nieuwstadt, Ann Arbor, Mich. (US); and Devesh Upadhyay, Canton, Mich. (US) | ||
| Assigned to Ford Global Technologies, LLC, Dearborn, Mich. (US) | ||
| Filed on Jul. 28, 2006, as Appl. No. 11/460,704. | ||
| Prior Publication US 2008/0022677 A1, Jan. 31, 2008 | ||
| This patent is subject to a terminal disclaimer. | ||
| Int. Cl. F02B 33/44 (2006.01); F02M 25/07 (2006.01); G06F 7/00 (2006.01); G06F 17/00 (2006.01); G01M 19/00 (2006.01) | ||
| U.S. Cl. 60—605.2 [123/568.21; 701/108; 701/34; 73/118.2] | 15 Claims |
| 1. A method for diagnosing a degradation of a first mass flow sensor in an engine, the engine also including a first and second
exhaust gas recirculation system, a turbocharger, a first exhaust gas recirculation system (EGR) coupled between the engine
intake and exhaust on a high pressure side of the turbocharger, a second EGR coupled between the engine intake and exhaust
on a low pressure side of the turbocharger, an EGR valve located in the second EGR, the first mass airflow sensor located
in an intake manifold upstream of the second EGR inlet, a second mass airflow sensor located in an intake manifold downstream
of the second EGR inlet and upstream of the first EGR inlet and upstream of the turbocharger, the method comprising:
adjusting the second EGR valve position to introduce an EGR perturbation;
measuring a flow in the inlet of the second EGR using the first mass airflow sensor, said flow including said perturbation;
and
diagnosing a degradation of the first sensor based on a deviation between an expected flow through the first mass airflow
sensor and the measured flow by the first mass airflow sensor.
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