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DOE OSTI · 1117647

Diagnostic for two-mode variable valve activation device

Fedewa, Andrew M
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Abstract

A method is provided for diagnosing a multi-mode valve train device which selectively provides high lift and low lift to a combustion valve of an internal combustion engine having a camshaft phaser actuated by an electric motor. The method includes applying a variable electric current to the electric motor to achieve a desired camshaft phaser operational mode and commanding the multi-mode valve train device to a desired valve train device operational mode selected from a high lift mode and a low lift mode. The method also includes monitoring the variable electric current and calculating a first characteristic of the parameter. The method also includes comparing the calculated first characteristic against a predetermined value of the first characteristic measured when the multi-mode valve train device is known to be in the desired valve train device operational mode.

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BibTeXRIS

Fedewa, Andrew M. 2014-01-07. Diagnostic for two-mode variable valve activation device. https://www.osti.gov/biblio/1117647

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