Valvetrain fault indication systems and methods using engine misfire

• US 9,133,775 B2
• Filed: 08/21/2012
• Issued: 09/15/2015
• Est. Priority Date: 08/21/2012
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Betz, Brian E., Miller, Hugh William
• Primary Examiner(s): Cronin, Stephen K
• Assistant Examiner(s): Scharpf, Susan E
• Application Number:
  US13/590,369
• Publication Number:
  US 20140053809A1
• Time in Patent Office: 1,120 Days
• Field of Search: 701/101, 701/102, 701/105, 701/115, 701/29.1, 701/29.2, 701/29.7, 701/29.8, 701/29.9, 701/30.1, 701/30.3, 701/30.5, 701/30.8, 701/30.9, 701/31.1, 701/31.2, 701/31.4, 12340612-40614, 12340616-40619, 12340626-40627, 123/406.41, 731/147.2, 731/142.6
• US Class Current: 1/1
• CPC Class Codes: F01L 13/0031 by modification of tappet or pushrod length
• CPC Class Codes: F01L 13/0036 the valves being driven by two or more cams with different shape, size or timing or a single cam profiled in axial and radial direction
• CPC Class Codes: F01L 2820/04 Sensors
• CPC Class Codes: F01L 35/00 Lift valve-gear or valve arrangements specially adapted for machines or engines with variable fluid distribution drive, adjustment during operation, tripping-gear, reversing-gear, use of working pistons or piston-rods as valves or as valve-supporting elements, valve-gear or valve arrangements peculiar to free-piston machines or engines F01L15/00 - F01L31/00
• CPC Class Codes: F02D 13/00 Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing
• CPC Class Codes: F02D 13/02 during engine operation
• CPC Class Codes: F02D 13/0207 changing valve lift or valve lift and timing
• CPC Class Codes: F02D 13/0219 by shifting the phase, i.e. the opening periods of the valves are constant
• CPC Class Codes: F02D 2041/001 for engines with variable valve actuation
• CPC Class Codes: F02D 2200/1015 Engines misfires
• CPC Class Codes: F02D 35/027 using knock sensors
• CPC Class Codes: F02D 41/0002 Controlling intake air
• CPC Class Codes: F02D 41/221 relating to the failure of actuators or electrically driven elements
• CPC Class Codes: F02P 5/1521 with particular means during a transient phase, e.g. starting, acceleration, deceleration, gear change
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A system for a vehicle includes a misfire indication module, a valve control module, and a fault indication module. The misfire indication module selectively indicates that misfire occurred within a cylinder of an engine. The valve control module controls lifting of a valve of a cylinder of the engine and, in response to the misfire indication module indicating that misfire occurred within the cylinder, transitions lifting of the valve from one of a low lift state and a high lift state to the other one of the low lift state and the high lift state. The fault indication module selectively indicates that a fault is present in a variable valve lift (VVL) mechanism of the cylinder based on whether the misfire indication module indicates that misfire occurred within the cylinder after the transition to the other one of the low lift state and the high lift state.

Claims

1. A system for a vehicle, comprising:

a first electronic circuit that selectively indicates that a coefficient of variation (COV) of indicated mean effective pressure (IMEP) of a cylinder of an engine is greater than a predetermined value;

a second electronic circuit that controls lifting of a valve of the cylinder of the engine and that, in response to the first electronic circuit indicating that the COV of IMEP of the cylinder is greater than the predetermined value, transitions lifting of the valve from one of a low lift state and a high lift state to the other one of the low lift state and the high lift state; and

a third electronic circuit that selectively indicates that a fault is present in a variable valve lift (VVL) mechanism of the cylinder based on whether the first electronic circuit indicates that the COV of IMEP of the cylinder is greater than the predetermined value after the transition to the other one of the low lift state and the high lift state.

2. The system of claim 1 wherein the third electronic circuit indicates that the fault is present in the VVL mechanism when the first electronic circuit does not indicate that the COV of IMEP of the cylinder is greater than the predetermined value after the transition to the other one of the low lift state and the high lift state.

3. The system of claim 2 wherein the third electronic circuit further indicates that the valve is stuck operating in the one of the low lift state and the high lift state when the first electronic circuit does not indicate that the COV of IMEP of the cylinder is greater than the predetermined value after the transition to the other one of the low lift state and the high lift state.

4. The system of claim 2 wherein the third electronic circuit further indicates that the fault is associated with the cylinder when the first electronic circuit does not indicate that the COV of IMEP of the cylinder is greater than the predetermined value after the transition to the other one of the low lift state and the high lift state.

5. The system of claim 2 wherein the third electronic circuit indicates that the fault is not present in the VVL mechanism when the first electronic circuit indicates that the COV of IMEP of the cylinder is greater than the predetermined value after the transition to the other one of the low lift state and the high lift state.

6. The system of claim 1 wherein the third electronic circuit sets a predetermined diagnostic trouble code (DTC) in memory when the fault is present in the VVL mechanism.

7. The system of claim 6 further comprising a fifth electronic circuit that monitors the memory and that illuminates a malfunction indicator lamp in response to the setting of the predetermined DTC.

8. The system of claim 1 further comprising a sixth electronic circuit that selectively adjusts spark timing of the cylinder in response to the first electronic circuit indicating that the COV of IMEP of the cylinder is greater than the predetermined value,

wherein, in response to the first electronic circuit indicating that the COV of IMEP of the cylinder is greater than the predetermined value, the second electronic circuit further selectively adjusts at least one of intake camshaft phasing and exhaust camshaft phasing.

9. The system of claim 1 wherein the first, second, and third electronic circuits include or are a part of at least one of:

an Application Specific Integrated Circuit (ASIC);

a combinational logic circuit;

a field programmable gate array (FPGA); and

a processor, memory, and code.

10. A method for a vehicle, comprising:

selectively indicating that a coefficient of variation (COV) of indicated mean effective pressure (IMEP) of a cylinder of an engine is greater than a predetermined value;

controlling lifting of a valve of the cylinder of the engine;

in response to an indication that the COV of IMEP of the cylinder is greater than the predetermined value, transitioning lifting of the valve from one of a low lift state and a high lift state to the other one of the low lift state and the high lift state; and

selectively indicating that a fault is present in a variable valve lift (VVL) mechanism of the cylinder based on an indication of whether the COV of IMEP of the cylinder is greater than the predetermined value after the transition to the other one of the low lift state and the high lift state.

11. The method of claim 10 further comprising indicating that the fault is present in the VVL mechanism in response to an indication that the COV of IMEP of the cylinder is not greater than the predetermined value after the transition to the other one of the low lift state and the high lift state.

12. The method of claim 11 further comprising indicating that the valve is stuck operating in the one of the low lift state and the high lift state in response to the indication that the COV of IMEP of the cylinder is not greater than the predetermined value after the transition to the other one of the low lift state and the high lift state.

13. The method of claim 11 further comprising indicating that the fault is associated with the cylinder in response to the indication that the COV of IMEP of the cylinder is not greater than the predetermined value after the transition to the other one of the low lift state and the high lift state.

14. The method of claim 11 further comprising indicating that the fault is not present in the VVL mechanism in response to a second indication that the COV of IMEP of the cylinder is greater than the predetermined value after the transition to the other one of the low lift state and the high lift state.

15. The method of claim 10 further comprising setting a predetermined diagnostic trouble code (DTC) in memory when the fault is present in the VVL mechanism.

16. The method of claim 15 further comprising:

monitoring the memory; and

illuminating a malfunction indicator lamp in response to the setting of the predetermined DTC.

17. The method of claim 10 further comprising:

selectively adjusting spark timing of the cylinder in response to the indication that the COV of IMEP of the cylinder is greater than the predetermined value; and

selectively adjusting at least one of intake camshaft phasing and exhaust camshaft phasing in response to the indication that the COV of IMEP of the cylinder is greater than the predetermined value.