1. Copyright 2001 AST Making Driveability Profitable ! Instructor: John Forro

2. Copyright 2001 AST Why do we lose money ? What is our ROI? What type of tech? How do we charge? How long does it take? What is our true profit? What about the risks involved? Can everyone do it?

3. Copyright 2001 AST What is our return on investment ? ROI is greater then any other type of work performed! Training, equipment and information systems are very costly investments, are we getting the most out of them? How long should it take to pay back our investment?

4. Copyright 2001 AST What type of technician is needed for driveability work ? The technician needs to be very highly skilled, stubborn and extremely dedicated. A true class “A” tech. How much will this lad cost us? Does your shops driveability tech truly make more money for the shop then your gravy guy?

5. Copyright 2001 AST How does your shop charge for this type of work? How does your shop charge? Most shops charge 1- hour’s diagnostic time. How long is spent on diagnosing? Could your money tree use some water?

6. Copyright 2001 AST How long should MOST driveability diagnostic work take? How long does a typical front brake job take when replacing pads and rotors with slip on rotors? What is you charge for this procedure? Did you double your labor time spent? Do you double your labor time spent on diagnostic work?

7. Copyright 2001 AST What is our true profit? Are we selling parts? Are we selling maintenance? Are we at least doubling our labor time? What jobs did we miss out on while doing this job? Are we on a recipe for failure?

8. Copyright 2001 AST What about risks involved? Do we always diagnose the car in the time allotted? Do we always fix the job right the first time? Does the customer always allow us to repair the vehicle. What about the elements?

9. Copyright 2001 AST What are the answers to these dilemmas? Don’t do driveability work. Sell more maintenance while doing our diagnostic work. Diagnose in a half hour or less!!!!!

10. Copyright 2001 AST Can everyone do this? Practice these new skills that we will cover. Think outside of the box! Work as a team!!!!

11. Copyright 2001 AST The approach Customer /PCM interrogation Road test Review codes/data stream Review movie/freeze frame Visual inspection Learn what you don’t know Quick-check tests Circuit/component diagnostics Road test vehicle performing any necessary drive cycles.

12. Copyright 2001 AST Typical lab scope screen Volt Division Grid Time Division Grid x Trigger Level

13. Copyright 2001 AST Definitions Coupling Amplitude Shape Duty Cycle Pattern Frequency Glitch Noise Slope Trigger Level

14. Copyright 2001 AST Coupling Coupling describes the type of signal being sampled: an A/C signal or a D/C signal. AC Signal DC Signal

15. Copyright 2001 AST Amplitude Amplitude refers to the overall height of the signal. Every component must reach a specific height before the PCM can recognize the signal!

16. Copyright 2001 AST Shape This term is used to describe the overall signature of an electronic signal, with its unique curves or look. Shape Characteristic

17. Copyright 2001 AST Duty cycle This is a term used to define the on or off time of a given signal. Duty Cycle

18. Copyright 2001 AST Pattern or synchronization Pattern or Synchronization pulses indicate component location or trigger a sequence of events to make them occur in the correct order.

19. Copyright 2001 AST Frequency This is a term which simply means the amount of times a signal repeats itself in a 1 second time frame.

20. Copyright 2001 AST Glitch This term is used to describe an intermittent malfunction in either the circuit or component being tested. Glitch

21. Copyright 2001 AST Noise This term is used to refer to unwanted electrical interference in a sensor’s voltage signal. This is usually caused by high current devices such as ignition components or alternators that generate strong magnetic disturbance that is transferred to the signal wire.

22. Copyright 2001 AST Slope Slope determines whether or not the scope will trigger on a voltage that is going from negative to positive or from positive to negative. Use this scope adjustment when you place the trigger point, depending on how you want the trigger to respond to voltage changes in the circuit being tested.

23. Copyright 2001 AST Trigger level Trigger level sets the voltage threshold that the scope must see to start displaying the waveform. Trigger level is represented by a small x on the left hand side of the screen.

24. Copyright 2001 AST Preliminary mechanical tests Check the levels Visual inspection Vacuum reading Compression test Cylinder leakage test Do you do these tests on most cars? Why not?

25. Copyright 2001 AST

28. Drivers seat diagnostics The interface decision PCM strategies Trouble code retrieval Diagnostic help Main inputs Parameter diagnostics

29. Copyright 2001 AST The scan tool Temperature RPM Load Demand O2 Fuel trim / integrator- block learn

30. Copyright 2001 AST Trouble code diagnostics The next time you get a trouble code try comparing the faulty component to a similar/related component such as the one displayed here. This could eliminate time consuming flow charts and false code diagnostics!

31. Copyright 2001 AST New age information

32. Copyright 2001 AST Scope tips and tricks Learn all the functions Choose best possible locations for hook ups Use PCM strategies Take up full screen ! Check sensor/actuator and PCM operation dynamically.

33. Copyright 2001 AST We need to know if there is a drain on the battery, but if we disconnect the cable and use our amp meter, we may turn on some unwanted lights. What can we do? Attach your low amp probe around the negative battery cable. Remember to zero your probe! This calculates to over a half an amp drain, using the 10mv = 1 amp scale.

34. Copyright 2001 AST The ignition system All problems can be found by interpret ting these patterns. Use fast scope. Test under load

35. Copyright 2001 AST Normal primary ignition pattern 100 volts per division & 2 milliseconds per division Transistor Turn On Current Limiting Resistor Primary Off Dwell Coil Oscillations

36. Copyright 2001 AST Explanation of operation

37. Copyright 2001 AST Primary signal areas of concern 100 volts per division & 2 milliseconds per division Transistor Turn On Current Limiting Resistor Primary Off Dwell Coil Oscillations

38. Copyright 2001 AST Typical bad module

39. Copyright 2001 AST Secondary pattern relationship Represents the amount of voltage needed to jump the gap. Represents the voltage requirement over the time or duration of the spark.

40. Copyright 2001 AST Secondary ignition pattern preliminaries Imagine if we straightened out the firing and spark line like a piece of rope. Lets say that the total voltage of that rope was 20 K volts. If it took as much energy to jump the gap as it took to maintain the gap, the pattern would appear to be equally proportioned. Remember, we bend the rope in a L shape Now imagine for a moment that it took more energy to jump the gap then normal. This is typical of a very lean condition. We will no longer have as much available voltage to keep the plug firing. Think of it as if we pulled one side of the rope, the other will get shorter! This would most likely cause a misfire. Finally the opposite holds true if we require very little voltage to jump the gap, we will then have a great deal of voltage left to maintain the spark. This is typical of a very rich or no compression condition.

41. Copyright 2001 AST Normal secondary pattern

42. Copyright 2001 AST Spark line sloping up

43. Copyright 2001 AST Spark line sloping down

44. Copyright 2001 AST Turbulence

45. Copyright 2001 AST Spark line has dippity-doo

46. Copyright 2001 AST What could be wrong?

47. Copyright 2001 AST Primary current/voltage signals

48. Copyright 2001 AST

49. Current ramping diagnostics

50. Copyright 2001 AST Secondary ramp diagnostics

51. Copyright 2001 AST Real world ramp diagnostics

52. Copyright 2001 AST

53. Secondary cheat sheet all cylinders High Firing KV 4Lean Condition 4Wide Rotor To Cap Gap Normal Firing KV/ Short Burn Times 4Coil Wire or Connections 4Rotor Wrong or Misaligned 4Coil or Saturation Problem * Spark output with a spark tester installed should be at least 20,000 volts (20 KV) with a burn time duration of at least 7ms!

54. Copyright 2001 AST Secondary cheat sheet single cylinder High Firing Voltage Peaks/Short Burn Time 4Open Wire 4Wide Plug Gap 4Corroded Secondary Connections Low Firing Voltage Spikes/Long Burn Time 4Fouled Plug 4Carbon Tracked Cap 4Damaged Secondary Plug Wire Insulation Allowing Spark to Short to Ground Pull wire to see if internal or external problem!

55. Copyright 2001 AST The fuel system Check pressure Check volume Check amperage Current ramp Check fuel quality Check pump speed

56. Copyright 2001 AST Fuel tests Use today’s testing procedures. If you must do “cave” testing, make sure you at least have ½ pint in 30 seconds.

57. Copyright 2001 AST New tests

58. Copyright 2001 AST What is new ? Tests pressure Tests volume Tests dead head Tests injectors Statically/dynamically Tests injector flow rates Tests fuel pump amperage and speed

59. Copyright 2001 AST Mastering Techniques Remember, we don’t learn how to use any of these tests fixing broke cars! You must learn on good cars!!!!!!

60. Copyright 2001 AST What we do….. Nation wide training National account training Curriculim development Automotive video training tapes Write and publish automotive repair manuals Local lemon law vehicle inspector Equipment distributor for the following companies: 1.Hickok/Waekon 2.Interro 3.MPC wiring diagram cd’s Repair problem vehicles for local shops

61. Copyright 2001 AST Thank You ! I hope to see you all again real soon! 0 items $0.00 store community library services hot tools credit Library To order by phone 1-877-9-Ontool or 1-877-966-8665 7:00 a.m. - 5:00 p.m. PST Monday through Friday home home | my account | help | contact us | about us my account help contact us about us Copyright © 2000-2001 Ontool, Inc. Terms of use and privacy statementsTerms of use and privacy statements