Method and device for diagnosing deviations in a single cylinder lambda control

US9188073B2 · kind B2 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Lu Chen · Bietigheim-Bissingen, DE
• Eberhard Schnaibel · Hemmingen, DE
• Andreas Koring · Ludwigsburg, DE
• Richard Holberg · Stuttgart, DE
• Michael Fey · Wiernsheim, DE

Key dates

• Filing date: Nov 5, 2010
• Grant date: Nov 17, 2015
• Expiry date: Jun 11, 2031

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02D2041/1432
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

The invention relates to a method and device for diagnosing deviations in a single cylinder lambda control in an internal combustion engine having at least two cylinders and an exhaust gas sensor designed as a broadband lambda sensor, wherein a pump current is evaluated by means of a pump cell and the pump current is used at least temporarily for an individual cylinder lambda control. According to the invention, a pump voltage or a pump voltage change is determined via the pump cell in addition to the pump current and the value is transmitted to a diagnosis apparatus. Deviations in the single cylinder lambda control can thus be better diagnosed without additional material expense according to the invention, which provides advantages in particular in respect of tightened rulemaking in on-board diagnosis. A preferred application of the method is the use in internal combustion engines having multi-bank exhaust systems.