WS8 Primary & Secondary Ignition Patterns

Make Toyota Corolla 4A-FE
Warning: Ignition coils create high voltage. It can be dangerous, so avoid getting too close to ignition parts when engine is running. Make your connections when the engine is off, and then keep your distance when the engine is running. Even some primary voltage is high enough
to stop a “Pacemaker”.
Also: Do not run engines with secondary ignition HT leads “open circuit”. Make sure they are grounded to engine through a spark plug, grounding wire, or spark tester.
If you have problems with the task, see you lecturer for help.

1.0 Primary Voltage Patterns
1.1 Set up a lab scope or ignition oscilloscope to view the primary ignition pattern (in parade or display mode) on your lab scope, with the engine warmed up and idling.
1.2 Record the average Firing Voltage (or “Step Up voltage) for each cylinder in the chart below. Some variation is normal, just pick the average. If you don’t understand what this is, review the resource information available.
1.3 Record the average Burn Voltage for each cylinder in the chart below.
1.4 Record the average Burn Time in milliseconds for each cylinder in the chart below.
1.5 Record the average Dwell Time for each of the cylinders in the chart below.

1.6 Are all these primary ignition voltage readings normal? Yes.
Please discuss what is normal and what causes it?
Obviously each cylinder have the same pattern, if we notice carefully only cylinder 1 have little bit different other about after burning time, so far I can say it is normal and have back EMF. May be causing the spark plug worn.  

Cyl 1	Cyl 2	Cyl 3	Cyl 4	Primary Ignition
250+	250+	250+	250+	Firing Voltage (V)
40.7	40.7	40.7	40.7	Burn Voltage (V)
1.01	1.01	1.01	1.01	Burn Time(ms)
5.35	5.25	5.41	5.45	Dwell Time(ms)

1.7 Draw or photograph the Primary Ignition oscilloscope parade pattern from your scope into the box below. Do it carefully and show the detail you need to see for diagnosis.

1.8 Discuss what the primary display or parade pattern emphasizes for diagnosis. What can it help you see?

From the oscilloscope above:

Point A is Dwell time: primary coil is grounded and the current coming through to the coil to charge the magnetic field.

Point B is Firing voltage: the magnetic field collapse in the primary coil and create high voltage to cross jump between electrode to the ground.

Point C is burn time: time is needed for energy dissipated.

Point D is Oscillation.
1.10 Some scopes have the facility to use raster or stacked display. How could this help you to diagnose a fault. What can you see more clearly?

Possible of misfiring, bad earth, checking the burning time and we can compare the electrode firing on the spark plug for each cylinder. All these effect to engine performance.

2.0 Secondary Voltage Patterns.
2.1 Set up your ignition oscilloscope or lab scope to view the secondary ignition patterns on your lab scope, with the engine warmed up and idling. (Use parade mode or individual mode on each different cylinder, depending on scope available.)
2.2 Record the average Firing Voltage (or “Step Up voltage) for each cylinder in the chart below. Some variation is normal, just pick the average. If you don’t understand what this is, review the resource information at the back of this worksheet.
2.3 Record the average Burn Time for each cylinder in the chart below. Are all these secondary ignition voltage readings normal? Yes. 
Cylinder 1:

Firing Voltage: 6.4KV and Burn Time: 1.39ms

Cylinder 2:

Firing Voltage: 5.2KV and Burn Time: 1.32ms
Cylinder 3:

Firing Voltage: 6.2KV and Burn Time: 1.19ms

Cylinder 4:

Firing Voltage: 6.1KV and Burn Time: 1.45ms

2.3 Record the average Burn Time for each cylinder in the chart below. Are all these secondary ignition voltage readings normal? Yes. 
Discuss what is happening in the pattern and what it is telling you about the ignition system.
To create the spark jump across from electrode to ground need high voltage and short time.

2.5 Do a Snap Acceleration (don’t damage the engine by revving too high or for too long) and record in the chart below how high the Firing Voltage (KV) went under Snap Acceleration.

The pattern below showing one of 4 cylinder:

Cyl 1	Cyl 2	Cyl 3	Cyl 4	Secondary Ignition
12.1	12.3	14.1	15.2	Firing Voltage (KV)
0.22	0.14	0.12	0.15	Burn Time (ms)
12	15	14	15	Snap Acceleration(KV)

2.6 Are all these Snap Acceleration secondary ignition voltage readings normal? Yes.

Discuss what is happening and what the pattern is telling you.
When we snap acceleration, fuel and air more coming than idle, at the time electron need energy to jump across, automatically firing voltage going higher and burning time less and less. Why less? because the energy burned will quickly disappear. 

2.7 Draw or photograph the Secondary Ignition lab scope pattern while idling from your scope into the box below. Do it carefully and show the detail you need to see for diagnosis.

2.8 If you can safely do this, (with the engine stopped), gently disconnect one spark plug wire, and short to the engine with a jumper wire. Which cylinder number did you short? 4
2.9 Start the engine and let it idle (for only a short time.) Record the new Firing Voltage and Burn Time for all the cylinders in the chart below.

Cyl 1	Cyl 2	Cyl 3	Cyl 4	Secondary Ignition (one cylinder grounded)
6.8	7.1	7.1	16.9	Firing Voltage (KV)
1.45	1.32	1.37	0.7	Burn Time (ms)

2.10 Draw or photograph the shorted Secondary Ignition waveform you see now on your scope.

2.11 Discuss what is happening in the shorted ignition pattern and how the ignition pattern tells you what it is happening in the ignition system.

On cylinder no 4 firing voltage higher and the burning time shortest than other 3 because the ground  wire has been shorted to the engine and in the same time need high voltage to push or force the spark across, automatically burn time will be short.

2.12 Remove the ground wire and attach the spark plug wire back on the engine so it is normal again. Run the engine a bit to clear the spark plug.
2.13 Stop the engine and attach a spark tester to another spark plug wire. Start the engine and let it idle (for only a short time). 

Record the new Firing Voltage and Burn Time for all the cylinders in the chart below.

Cyl 1	Cyl 2	Cyl 3	Cyl 4	Secondary Ignition (Spark tester on one cylinder)
5.9	13.3	5.6	5.31	Firing Voltage (KV)
1.46	1.46	1.83	1.83	Burn Time (ms)

2.14 Draw or photograph the spark tester Secondary Ignition waveform you see now on your scope.

2.16 Discuss what happens to the ignition waveform when the spark tester is attached to the spark plug wire. What does it tell you about the ignition system.
We remove the spark plug wire from cylinder 2 and attached spark tester, The spark park tester gap can be adjusted, the picture above (wider gap) test for the second time after we test the small gap. The spark still jump across but need higher voltage and the burn time will be short.  The table above showing the firing voltage higher than other.

2.17 Remove the spark tester carefully, and put everything back together on the engine. Engine runs fine? Yes.
Note: remember, all the experiment above about string theory where is the firing voltage high and the burn time will be short. Vice-versa.

WS6 Oxygen Sensors on Vehicle

Make Toyota1ZZ
1.0 Locate Oxygen Sensor
1.1 Locate an oxygen sensor on your vehicle. Describe where it is located:

 After exhaust manifold.


1.2 How many wires for this oxygen sensor? 3 wires
1.3 Record the colors for each of the wires at the sensor side of the connector (not the ECU side of the connector). Then list the use of the wires. Usually a black or blue wire will be the O2 sensor signal, Grey may be the sensor ground. Heater power and ground are often white. But there may be other colors. You may have to consult a wiring diagram. Black for signal, white for heater and other white for ground.

1.4 What type of Oxygen Sensor is this?
This type is Zirconia switching sensor working on 0.1-1V

2.0 Back probe the Oxygen Signal Wire with a pin and connect to an oscilloscope. If you need help using the oscilloscope see your lecturer or other help sources. Check that you are connected to the Oxygen sensor signal: Run the engine and check that you are seeing a signal. Connected OK? Yes it is.


3.0 Watch and Record Oxygen Signal pattern at 2500 rpm. Let the engine warm up and enter closed loop so you see a normal cycling pattern. You may have to hold the rpm about 2500 for half a minute to go into closed loop.
3.1 Freeze your pattern and draw or photograph it onto the graph below: Note the voltage and time per division or scale next to the graph.

3.2 How high does the voltage go? 0.7V
3.3 How low does the voltage go? 0.02V
3.4 What is the average voltage? (Some oscilloscopes have functions that will calculate the average for you. If not, just guess.) 0.45V
3.5 How many “Cross Counts” does the signal have in 10 seconds? (One cross count is when it goes from high to low, or from low to high.) List here: 2
3.6 If the signal is not cycling normally, describe what the signal does:
Not cycling normal. It's still working well but not as I expected.
I would like expected the signal would be like the picture below:

Reference:

http://www.auto-facts.org/automotivescantool.html
The signal as above running rich roughly 0.8V-0.9V and lean 0.1V-0.2V. And the same amplitude and frequency.

4.0 Watch and Record Oxygen Signal pattern at Idle rpm. Let the engine warm up and enter closed loop so you see a normal cycling pattern. You may have to hold the rpm about 2500 for half a minute to go into closed loop. Then let the RPM come down to idle.
4.1 Freeze your pattern and draw or photograph it onto the graph below: Note the voltage and time per division or scale next to the graph.

4.2 How high does the voltage go? 0.8V
4.3 How low does the voltage go? 0.02V
4.4 What is the average voltage? (Some oscilloscopes have functions that will calculate the average for you. If not, just guess.) 0.4V
4.5 How many “Cross Counts” does the signal have in 10 seconds? (One cross count is when it goes from high to low, or from low to high.) List here: 1
4.6 If the signal is not cycling normally, describe what the signal does:
Not cycling normal. The pattern look like going down little bit before revv down. Should be the pattern curve down smoothly.


5.0 Make this Oxygen Sensor go rich by accelerating once or twice. (The fuel system should normally make the system go rich when you do a sudden acceleration.) Push on the  accelerator quickly but don’t let the rpm go high enough to hurt the engine.
(If you act like you will hurt the engine you will be asked to leave lab.) The signal should go over 0.85V.
5.1 Freeze your pattern as it goes rich and draw or photograph it onto the graph below: Note the voltage and time per division or scale next to the graph.

5.2 How high does the Oxygen sensor voltage go? 0.8V
5.3 If this signal is not going high normally, describe what the signal does:

I revv the engine 3 times make the engine running rich, output amplitude the pattern not really smooth, even that what we would be expected.

6.0 Make this Oxygen Sensor go lean by doing a sudden deceleration. Gently run the rpm up to about 3,000, and let the RPM drop suddenly. The fuel system should make the system go lean on deceleration. The signal should go below 0.2V.
6.1 Freeze your pattern as it goes rich and draw or photograph it onto the graph below: Note the voltage and time per division or scale next to the graph.

6.1 How low does the Oxygen sensor voltage go? 0.13V
6.2 If this signal is not going low normally, describe what the signal does:

The voltage nearly 0V, looks like normal or good sensor, lower than 0.2V. Will jump back to previous voltage after few second.

7.0 Measure the Response Time of the sensor. You want to know that the sensor can respond quickly to changes in the exhaust gas. The best way is to do a sudden acceleration, freeze the pattern, and measure how long it took the sensor to go from lean to rich.
7.1 Freeze your pattern as it goes suddenly rich from a lean condition and draw it into the graph below: Normally you want the voltage to go from below 0.2V to above 0.8V. in less than 100 ms. Note the voltage and time per division or scale next to the graph.

7.2 Measure how long the sensor took to go from lean to rich.
Use the cursors on the scope if necessary. Record how long the sensor took here: 50ms.

Discuss how a normal Zirconium oxygen sensor works: draw a picture below to help show how it works? 

Zirconia oxygen sensor is an impervious tube-shaped zirconia (zirconium oxide) element with a closed end and is coated externally and internally with porous metal electrodes, typically platinum. Above temperature 400°C, this sensor becomes an oxygen ion conductor, which results in a voltage being generated between the electrodes. The voltage is dependent upon the differences between the partial pressures of the oxygen in the sample and the oxygen in a reference gas (generally air).
Thus, with air on both sides of the cell, the output is zero. The reference electrode is negative with respect to the sample electrode for sample concentrations of oxygen higher than that of air and positive for concentrations less than that of air. Depending on the application either the internal or external electrode can be used as the reference. The output voltage is processed electronically to provide signals suitable for display or for process control purposes.

Reference:
http://www.hitech-inst.co.uk/pdfs/technical/oxygen_sensors.pdf

Discuss how good or bad this Oxygen Sensor is. What about it functions well or is faulty? Use detail and specific voltages in your discussion. Can it accurately tell the ECU how rich or lean the exhaust is?
I would say this is not really bad and far from good below than average. This O2 sensor still can read and give the signal to the ECU not even than I expected because have an interference and not give us the pattern smoothly.

WS5 Scan Tool Diagnostic

Make Toyota Model 1ZZ


1. Scan Tool Data
1.1 Find a vehicle which is appropriate for the scan tool.
1.2 Connect the scanner, power it on, follow the instructions and input the correct vehicle information it asks for so you can view the data.
1.3 Find the data for the information listed on the next page. Turn engine on to idle. Fill in the letters used to label the information and the value of that data. (For example, engine load information may be found under MAP, with a value of 3.6, listed in volts) Note: not all vehicles will support all information, just find as much as you can. If the engine won’t run, input the information with the key on, engine off.

 

Type of information (PID = Parameter Identification)	Letters to describe it E.g. TPS	Value of data	Units for data E.g. volts
Engine Load (how much air comes in)	AFM(MAF)	2.58	gm/s
Engine RPM	Engine Speed	695	RPM
Throttle angle	TPS	11	%
Engine coolant temperature	Coolant Temperature	89	C
Intake air temperature	Intake air Temperature	21	C
Fuel Injection opening pulse	Injector Pulse Width	2.6	mS
Transmission select position	Shift	4
Vehicle Speed	0	0	km/h
Oxygen sensor(s)	O2 Sensor B1 S1	0.375	V
Fuel Trim	Short Fuel Trim#1	-2.3	%
Idle control	IAC Duty ratio	37.5	%
Power steering condition	PS Signal	OFF
Air conditioning condition	A/C cut signal	ON
Exhaust Gas Recirculation (EGR)
Fuel Evap or Purge condition	EVAP VSV	OFF
Malfunction Indicator Light (MIL)	Warning Light/MIL	OFF
Barometric Pressure

2 Trouble Codes or Fault Codes
2.1 Find where the Codes are listed
2.2 Record any codes, and what system and condition they describe in the chart below Example: might be code number 21, for Throttle Position Sensor, signal voltage too low) If there are no codes listed, put “none”.

3 Lecturer put in Fault
3.1 Find your lecturer and have him create a fault under the hood (don’t look)

4 Record New Codes
4.1 Look up the codes now in the scan tool
4.2 Record the codes in the chart below. Also record what system is affected, and what condition is described.

The Faulty code P0120 TPS circuit malfunction.

5 Find What Data Has Changed
5.1 Look through the scan tool data to see what PIDs
(Parameter Identification of system voltages) have changed.
Which readings don’t make sense or don’t read what you would expect. Concentrate on the PIDs related to the codes.

The throttle position is 0% which means scan tools proof it.


6 Visual Inspection to find fault
6.1 Do a visual inspection under the hood to find where the problem is. Use information from the code to know where to look for the problem and what type of problem to look for.
Describe problem you found:
Obviously there was not problem. 

7 Repair fault
7.1 Plug back in the connector, or repair problem found
7.2 Describe what you did:
We can check by multi-meter, related to the TPS wires terminal from voltage reference, signal and grounding.


8 Clear Codes

 Recheck the code

The Faulty code P0120 TPS circuit malfunction did not come up again.

Discuss the importance live data when fault finding

Live data very important to trace and track the faulty on time so we can fix the problem straight away.

Explain the need for parameters when checking live data

Off course we need the parameter when using the scan tools for identify which is faulty one. Wrong parameter or reading causing make another problem.

Discuss how a scan tool can aid you when fault finding
The scan tools will telling us what the problem is from ECU and must remember scan tools is not perfect magic tools, sometimes scan tools read not exactly what the problem is but close to the faulty. In the car consist of several section, in each section there is few sensor, they are communicate each other for a reason.