Fca US LLC

Jacob Andrew Kohn

Ethan E Bayer

Zhijian James Wu

Brian P Gebby

Dung Kieu Lam

Steven J Gorgas

Kevin V Rafalo

Julian D John

Techniques for measuring cylinder pressure include receiving an analog cylinder pressure signal indicative of pressure in a cylinder of an engine and an angular position signal indicative of an angular position of the engine. The analog cylinder pressure signal is converted to a digital cylinder pressure signal by (i) windowing the analog cylinder pressure signal in the angle-domain using the angular position signal and (ii) sampling the windowed analog cylinder pressure signal in the time-domain, and the digital cylinder pressure signal is filtered in the time-domain to obtain a filtered digital cylinder pressure signal. A measured pressure in the angle domain is obtained by sampling the filtered digital cylinder pressure signal using the angular position signal, and operation of the engine is controlled using the measured cylinder pressure.

Systems and methods for real-time angle-domain measurement of filtered cylinder pressure

An engine system and method for variable valve lift (VVL) diagnostic techniques are provided. In one exemplary implementation, the techniques include receiving, at a controller, a camshaft position signal indicative of detected edges of teeth of a camshaft toothed member that is coupled to a camshaft of an engine. The camshaft is configured to actuate a VVL system, which is configured to control a lift of a valve of the engine. The techniques also include calculating, at the controller, a camshaft speed signal indicative of a rotational speed of the camshaft based on the camshaft position signal. A valve stuck index (VSI) value is then calculated, at the controller, based on the camshaft speed signal. The techniques also include determining, at the controller, whether the valve is stuck based on a comparison of the VSI value to a predetermined threshold.

Variable valve lift diagnostic techniques based on camshaft speed

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West Bloomfield, MI, United States of America

Jacob Andrew Kohn