Vehicle diagnostic tool-utilizing volumetric efficiency

• US 8,612,091 B2
• Filed: 04/16/2012
• Issued: 12/17/2013
• Est. Priority Date: 06/08/2006
• Status: Active Grant

• Current Assignee: Bernie C. Thompson, Neal R. Pederson
• Original Assignee: Bernie C. Thompson, Neal R. Pederson
• Inventors: Thompson, Bernie C., Pederson, Neal R.
• Primary Examiner(s): Black, Thomas
• Assistant Examiner(s): PAIGE, TYLER D
• Application Number:
  US13/447,492
• Publication Number:
  US 20130103253A1
• Time in Patent Office: 610 Days
• Field of Search: 701/29.9, 701/30.8, 701/30.9, 701/32.1, 703/8
• US Class Current: 701/32.9
• CPC Class Codes: G01M 15/04 Testing internal-combustion engines
• CPC Class Codes: G01M 15/05 by combined monitoring of two or more different engine parameters
• CPC Class Codes: G07C 5/0808 Diagnosing performance data testing of vehicles G01M17/00; testing of electrical installation on vehicles G01R31/005

Abstract

An analysis tool which extracts all the available parameter identifications (i.e. PIDS) from a vehicle'"'"'s power train control module for diagnostic decisions. This is done by checking these PIDS and other information (e.g., calculated PIDS, Break Points, charts and algorithms) in three states; key on engine off, key on engine cranking, key on engine running. In all three modes the tool is comparing the live data from PIDS and voltage to the other information (e.g, Break Points). If any of this data are outside the programmed values a flag is assigned to the failure or control problem. The relationship between a particular PID and its associated preprogrammed value(s) may be indicated by a light. The depth of the problem (if any) is conveyed by the color of the light. Also included are tests/charts for fuel trim, engine volumetric efficiency, simulated injector, power, catalyst efficiency, and engine coolant range.

Claims

1. A diagnostic method for an automotive Power Plant implemented with the aid of instrumentation including a microprocessor;

the Power Plant including components selected from the group including an engine of known displacement, a powertrain control module, an air induction system, an exhaust system and at least one sensor;

the microprocessor being programmed to extract parameter identification data (hereinafter “

PID data”

) from the powertrain control module;

the microprocessor also being programmed with one or more algorithms which permit the analysis of extracted PID data;

the method including the steps of;

a. acquiring at lease some PID data from the powertrain control module with the instrumentation;

b. determining the actual air flow through the engine with at least some of the acquired PID data;

c. determining the calculated air flow through the engine (hereinafter “

Calculated VE”

) with at least one of the one or more algorithms; and

d. using actual air flow and Calculated VE in determining if there is a problem with one or more components of the Power Plant.

2. The method as set forth in claim 1, wherein the step of acquiring PID data includes acquiring PID data selected from the group:

Absolute Throttle Position (hereinafter “

ATP”

) PID data, engine speed PID data, manifold absolute pressure (hereinafter “

MAP”

) PID data and mass air flow (hereinafter “

MAS”

) PID data.

3. The method as set forth in claim 2, wherein the step of acquiring PID data includes acquiring PID data selected from the group:

Calculated Load PID data, absolute load value PID data, command throttle actuator control PID data, engine coolant temperature PID data, and air temperature PID data.

4. The method as set forth in claim 1, wherein the step of determining actual air flow is also determined with the aid of at least one of the one or more algorithms.

5. The method as set forth in claim 4, wherein the one or more algorithms is a speed density algorithm to determine the actual air flow through the engine, wherein the step of acquiring PID data includes acquiring MAP PID data from the powertrain control module, and wherein the step of determining the actual air flow through the engine includes determining the actual air flow with the speed density algorithm and the MAP PID data.

6. The method as set forth in claim 5:

a. wherein the step of acquiring PID data includes acquiring RPM PID data from the powertrain control module;

b. further including the steps of determining (i) the displacement of the engine, (ii) the barometric pressure, and (iii) the temperature; and

c. wherein the step of determining the actual air flow through the engine with the speed density algorithm utilizes the acquired RPM and MAP PID data, the engine displacement, the barometric pressure and the temperature.

7. The method as set forth in claim 4, wherein the step of acquiring PID data includes acquiring ATP PID data, and wherein the step of determining the Calculated VE includes determining the Calculated VE with ATP PID data and the at least one of the one or more algorithms.

8. The method as set forth in claim 7:

wherein the step of acquiring PID data also includes acquiring RPM PID data from the powertrain control module;

further including the steps of determining (i) the displacement of the engine, (ii) the barometric pressure, and (iii) the temperature; and

wherein the step of determining the Calculated VE through the engine with the at least one of the one or more algorithms utilizes the acquired RPM and ATP PID data, the engine displacement, the barometric pressure and the temperature.

9. The method as set forth in claim 4, further including the step of comparing the actual air flow as determined with the aid of at least one of the one or more algorithms with the actual air flow as determined with at least some of the acquired PID data without the use of an algorithm.

10. The method as set forth in claim 9, wherein the step of acquiring PID data includes acquiring MAS PID data, and the MAS PID data is used to determine actual air flow without the use of an algorithm.

11. The method as set forth in claim 9, wherein the at least one of the one or more algorithms is a speed density algorithm to determine the actual air flow through the engine, wherein the step of acquiring PID data includes acquiring MAP PID data from the powertrain control module, and wherein the step of determining the actual air flow through the engine includes determining the actual air flow with the MAP data and the speed density algorithm.

12. The method as set forth in claim 1, wherein the step of determining if there is a problem includes comparing actual air flow with Calculated VE.

13. The method as set forth in claim 12, wherein the step of comparing actual air flow with Calculated VE includes graphing both the actual air flow and Calculated VE.

14. The method as set forth in claim 13, further including the step of overlaying the graphs of actual air flow and Calculated VE.

15. The method as set forth in claim 13, wherein the instrumentation includes a screen for displaying graphs of air flow in weight/unit of time vs. time and further including the step of displaying the graphs of actual air flow and Calculated VE on the screen.

16. The method as set forth in claim 15, wherein the step of displaying the graphs of actual air flow and Calculated VE includes overlaying one on the other in a manner that one can be distinguished from the other.

17. The method as set forth in claim 12, wherein the step of comparing actual air flow with Calculated VE includes:

a. providing a plurality of ranges of air flow (weight/unit of time) vs. engine speed (RPM), wherein no two of the plurality of ranges have the same range of air flow and the same range of engine speed; and

b. for at least one range of air flow vs. engine speed, determining the difference between actual air flow and Calculated VE.

18. The method as set forth in claim 17, wherein the difference between actual air flow and Calculated VE is determined for a plurality of ranges as air flow and engine speed are varied.

19. The method as set forth in claim 17, wherein the step of providing a plurality of ranges of air flow vs. engine speed includes providing a table representing ranges of air flow vs. ranges of engine speed.

20. The method as set forth in claim 17, wherein the step of providing a plurality of ranges includes providing a table divided into a number of cells, wherein no two cells have the same range of air flow and same range of engine speed.

21. The method as set forth in claim 20, wherein the step of comparing the actual air flow through the engine with the Calculated VE includes the step of determining the percentage difference between the actual air flow and the Calculated VE at various air flows and engine speeds and assigning each determined percentage difference to a cell in the table depending on the engine speed and air flow at which such percentage difference was determined.

22. The method as set forth in claim 21, wherein the percentage differences between the actual air flow and the Calculated VE constitute a range of values, and further including the step of dividing such range of values into a series of sub-ranges, and assigning each sub-range a distinct code.

23. The method as set forth in claim 22, further including the step of assigning to each determined percentage difference its positive (“

+”

) or negative (“

−

”

) character.

24. The method as set forth in claim 23, further including:

a. the step of providing a first code for values between −

A and +A;

b. the step of providing a second code for values between −

A and −

B and between +A and +B, wherein the absolute value of B is greater than the absolute value of A; and

c. the step of providing a third code for values between −

B and −

C or between +B and +C, wherein the absolute value of C is greater than the absolute value of B.

25. The method as set forth in claim 24:

a. wherein the instrumentation is provided with a screen; and

b. wherein the step of assigning codes includes the step of assigning a different color to each of the sub-ranges.

26. The method as set forth in claim 25, further including the steps of:

a. assigning a first color to the range −

A to +A;

b. assigning a second color to the ranges −

A to −

B and +A to +B; and

c. assigning a third color to the ranges −

B to −

C and +B to +C.

27. The method as set forth in claim 26, further including the step of providing a fourth code for values greater than +C and less than −

C.

28. The method as set forth in claim 27, further including the steps of:

a. assigning a first color to the range −

A to +A;

b. assigning a second color to the ranges −

A to −

B and +A to +B;

c. assigning a third color to the ranges −

B to −

C and +B to +C; and

d. assigning a fourth color to values greater than +C and less than −

C.

29. The method as set forth in claim 12, wherein the step of using actual air flow and Calculated VE in determining if there is a problem with one or more components of the Power Plant includes determining the differences between actual air flow and Calculated VE as the speed of the engine changes.

30. The method as set forth in claim 29, wherein the step of acquiring PID data includes acquiring fuel trim PID data;

further including the step of determining the fuel trim from the fuel trim PID data and at least one of the one or more algorithms as the engine speed increases; and

further including the step of comparing the air flow differences with the fuel trim as the engine speed changes.

31. The method as set forth in claim 1, wherein the step of determining Calculated VE includes:

a. determining theoretical air flow (hereinafter “

TAF”

) with at least one of the one or more algorithms; and

b. determining Calculated VE from TAF with at least one of the one or more algorithms.

32. The method as set forth in claim 31, wherein the step of determining if there is a problem includes comparing actual air flow with Calculated VE.

33. The method as set forth in claim 32, wherein the step of comparing actual air flow with Calculated VE includes graphing both the actual air flow and Calculated VE.

34. The method as set forth in claim 33, wherein the step of comparing actual air flow with Calculated VE includes:

a. providing a plurality of ranges of air flow (weight/unit of time) vs. engine speed (RPM), wherein no two of the plurality of ranges have the same range of air flow and the same range of engine speed; and

b. for at least some of the ranges of air flow vs. engine speed, determining the difference between actual air flow and Calculated VE.

35. The method as set forth in claim 34, wherein the step of providing a plurality of ranges of air flow vs. engine speed includes providing a table representing ranges of air flow vs. ranges of engine speed.

36. The method as set forth in claim 35, wherein the step of providing a plurality of ranges includes providing a table divided into a number of cells, wherein no two cells have the same range of air flow and the same range of engine speed.

37. The method as set forth in claim 36, wherein the step of comparing the actual air flow through the engine with the Calculated VE includes the step of determining the percentage difference between the actual air flow and the Calculated VE at various air flows and engine speeds and assigning each determined percentage difference to a cell in the table depending on the engine speed and air flow at which such percentage difference was determined.

38. A diagnostic instrument for a Power Plant, the Power Plant including an engine and a powertrain control module, the instrument including:

a. a microprocessor programmed for collecting data from a Power Plant, including air flow and engine speed data from a running engine, and analyzing such data to determine the difference between actual air flow through the engine and the calculated air flow through the engine (“

Calculated VE”

) at various engine speeds and air flow rates; and

b. a means on which the differences between actual air flow and Calculated VE for a plurality of ranges of air flow vs. engine speed (wherein no two of the plurality of ranges have the same range of air flow and the same range of engine speed) can be presented to a user of the instrument.

39. The diagnostic instrument as set forth in claim 38, wherein the means for presenting includes a screen on which the differences between actual air flow through the engine and Calculated VE for the plurality of ranges of air flow vs. engine speed can be displayed.

40. The diagnostic instrument as set forth in claim 39, wherein the means for presenting includes a table having a first axis representing increasing values of actual air flow, a second axis representing increasing values of engine speed;

the table further including a plurality of cells, each cell representing a different range of actual air flow vs. engine speed.

41. The diagnostic instrument as set forth in claim 38, wherein the microprocessor is also programmed to graph both the actual air flow through the engine and the Calculated VE as the engine is running, and analyze such graphs.

42. The diagnostic instrument as set forth in claim 41, wherein the means for presenting includes a screen on which at least one of the differences between actual air flow through the engine and Calculated VE for the series of ranges of air flow vs. engine speed, and the graphs can be displayed.

43. The diagnostic instrument as set forth in claim 38, wherein the microprocessor is also programmed to collect and analyze engine load data from the Power Plant to determine fuel trim data as the engine is running at the various speeds, and wherein the instrument also includes a means on which fuel trim data at the various speeds and engine loads can be presented.

44. The diagnostic instrument as set forth in claim 43, wherein the means for presenting includes a screen on which at least one of the differences between actual air flow through the engine and Calculated VE for the series of ranges of air flow vs. engine speed, and the fuel trim data can be displayed.