METHOD FOR ON BOARD DIAGNOSTICS AND SYSTEM FOR ON BOARD DIAGNOSTICS

• US 20110153146A1
• Filed: 09/08/2008
• Published: 06/23/2011
• Est. Priority Date: 09/08/2008
• Status: Abandoned Application

• Current Assignee: Volvo Lastvagnar AB (Volvo AB)
• Original Assignee: Volvo Lastvagnar AB (Volvo AB)
• Inventors: Wikner, Stefan
• Application Number:
  US13/060,461
• Publication Number:
  US 20110153146A1
• Time in Patent Office: Days
• US Class Current: 701/29
• CPC Class Codes: F02B 37/22 by varying cross-section of exhaust passages or air passages , e.g. by throttling turbine inlets or outlets or by varying effective number of guide conduits F02B37/24 takes precedence
• CPC Class Codes: F02B 39/16 Other safety measures for, or other control of, pumps
• CPC Class Codes: F02D 2200/0402 the parameter being determined by using a model of the engine intake or its components
• CPC Class Codes: F02D 2200/0406 Intake manifold pressure
• CPC Class Codes: F02D 2200/0408 Estimation of intake manifold pressure
• CPC Class Codes: F02D 41/0007 for control of turbo-charged or super-charged engines control of the pumps per se F02B37/12
• CPC Class Codes: F02D 41/221 relating to the failure of actuators or electrically driven elements
• CPC Class Codes: F02M 26/05 High pressure loops, i.e. wherein recirculated exhaust gas is taken out from the exhaust system upstream of the turbine and reintroduced into the intake system downstream of the compressor
• CPC Class Codes: F02M 26/19 Means for improving the mixing of air and recirculated exhaust gases, e.g. venturis or multiple openings to the intake system
• CPC Class Codes: F02M 26/22 with coolers in the recirculation passage
• CPC Class Codes: G01M 15/09 by monitoring pressure in fluid ducts, e.g. in lubrication or cooling parts
• CPC Class Codes: G01M 15/14 Testing gas-turbine engines or jet-propulsion engines
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

In a method for on board diagnostics for detecting a charge air leakage in a vehicle, air is compressed by a turbine with variable geometry and fed to the combustion engine. Steps are performed of feeding compressed air to the engine without fuel supply to the engine; estimating a boost pressure from a current vane geometry of the variable geometry turbine; measure the actual boost pressure; and comparing the estimated boost pressure with the measured boost pressure.

Claims

1. A method for on board diagnostics for detecting a charge air leakage in a vehicle, wherein air is compressed by a turbine with variable geometry and fed to the combustion engine, comprising:

feeding compressed air to the engine without fuel supply to the engine;

estimating a boost pressure from a current vane geometry of the variable geometry turbine;

the measuring an actual boost pressure;

comparing the estimated boost pressure with the measured boost pressure.

2. The method according to claim 1, comprising determining if a leak is present if the difference between the measured and the estimated boost pressure is larger than a predetermined value.

3. The method according to claim 1, wherein the estimated boost pressure is determined during an operational state of engine braking of the engine.

4. The method according to claim 1, comprising determining the actual vane geometry of the turbine by monitoring a position of an actuator for varying the vane geometry of the turbine.

6. A system for an on board diagnostics method according to claim 1, comprising a calculating unit for determining an estimated boost pressure from a current vane geometry of a variable geometry turbine and comparing the estimated boost pressure with a measured boost pressure.

8. A computer comprising a computer program code for use in a method according to claim 1.

9. A computer according to claim 8 arranged to download the code when the computer is connected to the internet.

10. program product stored on a A non-transitory computer readable medium, comprising program code for use in a method according to claim 1.

5. The method according to claim 5, comprising extracting at least the measured boost pressure from an actual air mass flow through the engine.

7. A vehicle comprising a system according to claim 7.