Wasted Spark.
Coil primary
1= 0.7 Ohm
2=0.8 Ohms
3=0.6 Ohms
Coil secondary
1=12.2K ohms
2=12.3K ohms
3=12.3K ohms
Testing Ballast resistors
Part no: BR1
Resistance= 1.2 Ohms.
Standard Single tower coil
1. Wire up a ballast resistor in series with your coil primary winding values as shown in
the following diagram.
2. Connect an ammeter in series and note the current draw.
3. Measure and note the voltage drop across the ballast resistor.
4. Measure and note the voltage drop across the coil primary.
Current draw was 3.1A
Coil calculated voltage drop=6.51V
Coil measured voltage drop=10.6V
Ballast resistor calculated voltage drop=3.72
Ballast resistor measured voltage drop=1.3V
Sunday, November 14, 2010
WS7 Exhaust Gas Analysis
In the AIR
CO: 0%
HC: 0 ppm
CO2: 0.033%
O2: 21%
Start the engine measure when engine is cold.
CO: 0.07%
HC: 129 ppm
CO2: 15.11 %
O2: 0.33%
With the engine warming up
CO: 0.5%
HC: 100 ppm
CO2: 14.3%
O2: 0.48%
With engine at 2500 rpm
CO: 0.01%
HC: 17ppm
CO2: 15.18%
O2: 0.38%
Run the engine rich with propane and measure the results
CO: .011%
HC: 5 ppm
CO2: 15.16%
O2: 0.08
Make a vacuum leak and record the engine while running lean
CO: .004%
HC: 10ppm
CO2: 14.57
O2: 1.12%
The Lambda value was 1.053
Record the readings when accelerating.
CO: 0.039%
HC: 6ppm
CO2: 14.8%
O2: 0.52%
We were unable to complete experiment as power died.
CO: 0%
HC: 0 ppm
CO2: 0.033%
O2: 21%
Start the engine measure when engine is cold.
CO: 0.07%
HC: 129 ppm
CO2: 15.11 %
O2: 0.33%
With the engine warming up
CO: 0.5%
HC: 100 ppm
CO2: 14.3%
O2: 0.48%
With engine at 2500 rpm
CO: 0.01%
HC: 17ppm
CO2: 15.18%
O2: 0.38%
Run the engine rich with propane and measure the results
CO: .011%
HC: 5 ppm
CO2: 15.16%
O2: 0.08
Make a vacuum leak and record the engine while running lean
CO: .004%
HC: 10ppm
CO2: 14.57
O2: 1.12%
The Lambda value was 1.053
Record the readings when accelerating.
CO: 0.039%
HC: 6ppm
CO2: 14.8%
O2: 0.52%
We were unable to complete experiment as power died.
Saturday, November 13, 2010
WS3B Dual Pattern
Using a dual trace (two channels A/B) oscilloscope capture the following
components and plot them against each other
The following sensors are used for WS3B:
MAP (analogue voltage) against Injectors (petrol)
RPM (Hall digital crank or distributor) against Injectors (petrol)
Oxygen sensor against Injectors (petrol)
Ignition primary against Injectors (petrol)
Ignition primary voltage against Ignition primary current
MAP (analogue voltage) against Injectors (petrol)
components and plot them against each other
The following sensors are used for WS3B:
MAP (analogue voltage) against Injectors (petrol)
RPM (Hall digital crank or distributor) against Injectors (petrol)
Oxygen sensor against Injectors (petrol)
Ignition primary against Injectors (petrol)
Ignition primary voltage against Ignition primary current
MAP (analogue voltage) against Injectors (petrol)
Signal Name: MAP Sensor vs Injectors
Volt/division: 10V
Time/division: 5ms
This waveform is comparing injector to the MAP sensor. This waveform was taken at idle so the MAP sensor voltage did not change. The injector waveform is normal. If more throttle is applied then there will be more voltage at the MAP sensor and the injectors will be opening and closing faster than at idle.If the MAP voltage did not change then the injection speed would not change so the engine wouldn't run at optimal performance.
RPM (Hall digital crank or distributor) against Injectors (petrol)
The injector is just the normal waveform with charging voltage, PWM time, Back EMF then back to charging voltage. The CKP sensor is fluctuating at idle producing AC voltage. As the CKP voltage increasing and the amplitude this means the engine is rotating faster. So the injectors will open and close quicker.
Oxygen sensor against Injectors (petrol)
We were unable to have the waveforms on the same screen because of the digital oscilloscope .The injector is just the normal waveform with charging voltage, PWM time, Back EMF then back to charging voltage. The oxygen sensor is fluctuating from rich to lean.
Ignition primary against Injectors (petrol)
We were unable to have the waveforms on the same screen because of the digital oscilloscope .The injector is just the normal waveform with charging voltage, PWM time, Back EMF then back to charging voltage. The beginning of the ignition waveform is charging voltage. The Voltage then drops to 0V by the ECU/ Igniter. Next a Back EMF is caused which is 40V. Which is when the spark is created. Next is spark duration and coil oscillations and back to charging voltage.
These two compare because when there is fuel being injected , you need a spark to complete combustion and create any form of power. As injectors spray quicker a spark needs to be created quicker. If there was no spark or injection the engine would not run. Unless it was just no spark or injection on 1 cylinder or 2 cylinders for some engines.
We were unable to get a waveform using current as it wasn't supported by the oscilloscope.
This waveform is comparing injector to the MAP sensor. This waveform was taken at idle so the MAP sensor voltage did not change. The injector waveform is normal. If more throttle is applied then there will be more voltage at the MAP sensor and the injectors will be opening and closing faster than at idle.If the MAP voltage did not change then the injection speed would not change so the engine wouldn't run at optimal performance.
RPM (Hall digital crank or distributor) against Injectors (petrol)
Signal Time: RPM Sensor vs Injectors
Volt/division: 10V
Time/division: 10ms
The injector is just the normal waveform with charging voltage, PWM time, Back EMF then back to charging voltage. The CKP sensor is fluctuating at idle producing AC voltage. As the CKP voltage increasing and the amplitude this means the engine is rotating faster. So the injectors will open and close quicker.
Oxygen sensor against Injectors (petrol)
We were unable to have the waveforms on the same screen because of the digital oscilloscope .The injector is just the normal waveform with charging voltage, PWM time, Back EMF then back to charging voltage. The oxygen sensor is fluctuating from rich to lean.
Ignition primary against Injectors (petrol)
We were unable to have the waveforms on the same screen because of the digital oscilloscope .The injector is just the normal waveform with charging voltage, PWM time, Back EMF then back to charging voltage. The beginning of the ignition waveform is charging voltage. The Voltage then drops to 0V by the ECU/ Igniter. Next a Back EMF is caused which is 40V. Which is when the spark is created. Next is spark duration and coil oscillations and back to charging voltage.
These two compare because when there is fuel being injected , you need a spark to complete combustion and create any form of power. As injectors spray quicker a spark needs to be created quicker. If there was no spark or injection the engine would not run. Unless it was just no spark or injection on 1 cylinder or 2 cylinders for some engines.
We were unable to get a waveform using current as it wasn't supported by the oscilloscope.
Friday, November 12, 2010
WS3 Ocilloscope Patterns
These sensors and actuators are used for the general lab worksheet WS3:
You need to capture at least 7 patterns from the lists below:
Sensors
MAP (digital)
MAF (digital)
TPS (switch type)
RPM (ac magnetic crank or distributor)
RPM (cam or distributor)
RPM (Hall digital crank or distributor)
Oxygen sensor
Actuators:
Injectors (petrol)
Injectors (diesel)
Idle air (digital 2 wire)
Idle air (digital 3 wire, both channels)
Ignition timing control (digital or analogue)
Ignition primary
Ground noise
Alternator ripple
Alternator Ripple
This above waveforms show the alternator ripple for idle and under load. With headlights , Air con, Radio ect on. The Alternator produces AC voltage and current . The battery requires DC voltage and current to charge properly. Diodes located within the alternator rectify the AC to DC. However, a small amount of AC can still be present and no harm is done. Problems can develop when alternator diode faults permit unacceptable amounts of AC to pass into the electrical systems.
Ignition Primary
MAF sensor
This waveform is showing MAF voltage when accelerator was pressed and released slowly to create this waveform. This shows as more air enters the engine there is a larger voltage produced.
MAP sensor
Secondary ignition pattern
This waveform is from the secondary ignition off a b16A integra.
You need to capture at least 7 patterns from the lists below:
Sensors
MAP (digital)
MAF (digital)
TPS (switch type)
RPM (ac magnetic crank or distributor)
RPM (cam or distributor)
RPM (Hall digital crank or distributor)
Oxygen sensor
Actuators:
Injectors (petrol)
Injectors (diesel)
Idle air (digital 2 wire)
Idle air (digital 3 wire, both channels)
Ignition timing control (digital or analogue)
Ignition primary
Ground noise
Alternator ripple
Alternator Ripple
Signal Name: Alternator Ripple
Volt/division: 188mV
Time/division: 2.1ms
This above waveforms show the alternator ripple for idle and under load. With headlights , Air con, Radio ect on. The Alternator produces AC voltage and current . The battery requires DC voltage and current to charge properly. Diodes located within the alternator rectify the AC to DC. However, a small amount of AC can still be present and no harm is done. Problems can develop when alternator diode faults permit unacceptable amounts of AC to pass into the electrical systems.
Ignition Primary
Signal Name: Ignition Primary.
Volt/division: 20V
Time/division: 2ms
The beginning of the waveform is charging voltage. The Voltage then drops to 0V by the ECU/ Igniter. Next a Back EMF is caused which is 40V. Which is when the spark is created. Next is spark duration and coil oscillations and back to charging voltage.
Ground Circuit.
This shows a low amount of voltage in the earth circuit which in term means low resistance. Our voltage from the waveform was 0.006V which is very small. This is acceptable from the manufacturers specifications. Anything above 0.050V is considered excessive.
The beginning of the waveform is charging voltage. The Voltage then drops to 0V by the ECU/ Igniter. Next a Back EMF is caused which is 40V. Which is when the spark is created. Next is spark duration and coil oscillations and back to charging voltage.
Ground Circuit.
Signal Name: Ground Circuit
Volt/division: 0.5V
Time/division: 2ms
MAF sensor
Signal Name: MAF sensor
Volt/division: 2V
Time/division: 50ms
This waveform is showing MAF voltage when accelerator was pressed and released slowly to create this waveform. This shows as more air enters the engine there is a larger voltage produced.
MAP sensor
Signal Name: MAP Sensor
Volt/division: 2V
Time/division: 100ms
The beginning of this waveform was the MAP at idling voltage. When accelerator was pressed and released this waveform was created. This shows voltage is increased as more throttle is applied. The Map sensor produces a voltage created from the vacuum inside the intake manifold.The data is used to calculate air density and determine the engine's air mass flow rate, which in turn determines the required fuel metering for optimum combustion. At the end of the waveform it is back to idling voltage.
Secondary ignition pattern
Signal Name: Secondary Ignition
Volts/division: 4KV
Time/division: 3.4ms
This waveform is from the secondary ignition off a b16A integra.
The ignition secondary picture shown above in the waveform is a typical picture from an engine fitted with electronic ignition. The waveform is an individual secondary High Tension (HT) picture that can be observed one cylinder at a time.
The secondary waveform shows the voltage required to jump the plug's electrode (A), and (B) the length of time that the HT is flowing across the spark plug's electrode after its initial voltage to jump the plug gap. This time is referred to as either the ‘burn time’ or the ‘spark duration’.
In the illustration shown, it can be seen that the horizontal voltage line in the centre of the oscilloscope (C) is at fairly constant voltage of approximately 3 kV. This voltage is referred to as the Sparkline kV. This voltage is the voltage required to maintain the spark flow across the plug's electrode, and is determined primarily by the secondary resistance within the HT circuit. From the 0 ms point on the scope to point D is the spark duration, in this case around 1.0 milliseconds. The waveform is then seen to drop sharply into what is referred to as the ‘coil oscillation’ (E). The coil oscillation should display a minimum number of peaks (both upper and lower) and at least of 4 - 5 peaks should be seen. A loss of peaks on this oscillation shows that the coil needs substituting. An example of a faulty coil and the subsequent loss of oscillations can be seen in Fig 1.2. The oscillation seen at point (F) is called the ‘polarity peak’; this voltage will be of the opposite polarity to the plug firing voltage as this is created when the magnetic flux is initially built, or at the start of the dwell period.
http://www.pc-oscilloscopes.com/primary-vs-secondary.html
Magnetic Distributor.
Signal Name: RPM (Magnetic, Distributor)
Volt/division: 10V
Time/division: 10ms
This is the voltage created at idle. As frequency increases so does voltage and amplitude. If the engine RPM was increased voltage and amplitude would also be increased. This is AC voltage.This works with a magnet and a pick up coil. As the air gap/ distance from the magnet gets further away voltage gets lower and when it gets closer voltage gets higher. The engine will die if the ECU does not receive this signal.
This is the voltage created at idle. As frequency increases so does voltage and amplitude. If the engine RPM was increased voltage and amplitude would also be increased. This is AC voltage.This works with a magnet and a pick up coil. As the air gap/ distance from the magnet gets further away voltage gets lower and when it gets closer voltage gets higher. The engine will die if the ECU does not receive this signal.
Thursday, November 11, 2010
WS3A Ocilloscope Patterns
MAP Sensor
This waveform was taken during a sharp acceleration. The voltage increases when more throttle is applied. Where the waveform starts is point A that is idling voltage. where it increases is when more throttle is applied and the end on the waveform is idling voltage again.
A fault to stop the MAP sensor working could be a broken connection, it could be open circuit inside the MAP sensor. Could have excessive resistance in the wiring loom. There could be a wiring fault when it was connected.
MAF sensor
The beginning for the waveform point (A) is the MAF at idle. at point B when it is increasing this is when the throttle was applied and more air was allowed into the engine.At point C it would be back to idle voltage.An electrical fault could be the wire not heating up and resistance doesnt change so voltage would always be the same.In this situation the voltage would always be 1.7V and would not change. The effect of this would be the car would run in limp home mode and idle will fluctuate. The graph would look like a straight line with no movement from idle voltage.
TPS .
We didnt have a linear type so we used a potentiometer type. point A is 0.5V whcih is idle voltage. It slowly increases as more throttle is applied this is because resistance decreases as more throttle is applied. This is a variable resistor. The problem could be excessive resistance in the earth wire. So there would be less voltage at the TPS. So the ECU would not know how much the throttle was applied. So the engine would run rich.
ECT
This graph shows what happens to the ECT. It would be difficult to get a waveform showing the voltage changing. The ECT is a NTC thermistor. This means as temprature increasing resitance decreases. A problem again could be excessive resistance so the ECU would not recieve the correct voltage and would not know if the engine is hot or cold. If the ECT voltage didnt change stayed at 5V the engine would be constantly rich.
IAT
This graph shows that the IAT is NTC thermistor. resistance decreases with TEmprature. It would be difficult to get a waveform showing the voltage changing. Again the problem could be excessive ressistance within the circuit. This would mean the ECU would get incorrect signal voltage. This is how the ECU knows it is a cold start by comparing voltage to the ECT. if there was excessive ressitance the voltage would be lower.
MAF sensor
The beginning for the waveform point (A) is the MAF at idle. at point B when it is increasing this is when the throttle was applied and more air was allowed into the engine.At point C it would be back to idle voltage.An electrical fault could be the wire not heating up and resistance doesnt change so voltage would always be the same.In this situation the voltage would always be 1.7V and would not change. The effect of this would be the car would run in limp home mode and idle will fluctuate. The graph would look like a straight line with no movement from idle voltage.
TPS .
We didnt have a linear type so we used a potentiometer type. point A is 0.5V whcih is idle voltage. It slowly increases as more throttle is applied this is because resistance decreases as more throttle is applied. This is a variable resistor. The problem could be excessive resistance in the earth wire. So there would be less voltage at the TPS. So the ECU would not know how much the throttle was applied. So the engine would run rich.
ECT
This graph shows what happens to the ECT. It would be difficult to get a waveform showing the voltage changing. The ECT is a NTC thermistor. This means as temprature increasing resitance decreases. A problem again could be excessive resistance so the ECU would not recieve the correct voltage and would not know if the engine is hot or cold. If the ECT voltage didnt change stayed at 5V the engine would be constantly rich.IAT
This graph shows that the IAT is NTC thermistor. resistance decreases with TEmprature. It would be difficult to get a waveform showing the voltage changing. Again the problem could be excessive ressistance within the circuit. This would mean the ECU would get incorrect signal voltage. This is how the ECU knows it is a cold start by comparing voltage to the ECT. if there was excessive ressitance the voltage would be lower.
WS5 Scan Tool Diagnostics
Scan Tool readings.
Engine Load MAP 0.9 V
Engine RPM RPM 750 RPM
Throttle angle TPS 9 percent
Engine coolant ECT 85 Degrees celcious
Intake air temperature IAT 56 Degrees celcious
Fuel Injection opening pulse PWM 1.5 MS
Vehicle Speed VSS 0 KM/H
Oxygen sensor(s) 02 0.8V
Idle control IACV 265 mA
There were no faults as the car has no problems.
Create Faults
Engine Load MAP 0.9 V
Engine RPM RPM 750 RPM
Throttle angle TPS 9 percent
Engine coolant ECT 85 Degrees celcious
Intake air temperature IAT 56 Degrees celcious
Fuel Injection opening pulse PWM 1.5 MS
Vehicle Speed VSS 0 KM/H
Oxygen sensor(s) 02 0.8V
Idle control IACV 265 mA
There were no faults as the car has no problems.
Create Faults
3 MAP Voltage to high
6 ECT Voltage to high
7 TPS Voltage to low.
The problem was the MAP,ECT and TPS were all unplugged.
To repair I plugged the connectors back in.
Recheck
ECT 85 Degrees
MAP 0.9V
TPS 9 %
To clear the codes i disconnected the battery.
There where no error codes after disconnecting the battery.
Live data is usefull for finding intermitant faults.
Scan tool aids fault finding because it will tell you which sensor / circuit has a problem then you can diagnose it yourself. It saves checking multiple things just have to check the one with a problem.
WS8 Primary & Secondary Ignition Patterns
Dwell Time
11 Degrees all 4 cylinders
Burn Time
1.5ms All cylinders
Burn Voltage
25V Firing Voltage
300V.
Yes these readings are normal for the primary because the car runs good and there is no problems with the car. Dwell should be the same across all cylinders which it is. Firing voltage and burn time/voltage are good.
The parade pattern is good to know if the coil sparks weaker intermittently. It could help you for a intermittent missfire.
A stacked display can help diagnose because you can compare two waveforms.
Secondary Voltage Patterns.
Average firing voltage.
Average burn time.
The ignition voltages are normal because the car runs good.
Short sharp acceleration.
BURN TIMEFiring Voltage
All the above readings were at 5000RPM. The pattern are showing us this ignition system is in good condition.
Secondary Ignition Waveform.
Shorted Cylinder 4.
Firing Voltage
1=4-6kV
2=4KV
3=6-7KV.
4=9KV.
Burn Time
1=0.6MS
2=1.3MS
3-1.2MS
4=1.3MS
Shorted Waveform
When it is shorted the voltage should increase and you can see by the above waveform. This shows the ignition system is good.
Spark plug tester.
Cylinder 1. 5-7KV, 3.5ms Burn time
Cylinder 2. 4-6KV 0.8 ms Burn time
Cylinder 3 -2-3KV 1.4ms Burn Time
Cylinder 4 2-4KV 1.2MS burn time.
The spark plug tester was in plug one. the gap is larger in the tester so a higher voltage is produced. We could see a good spark.
11 Degrees all 4 cylinders
Burn Time
1.5ms All cylinders
Burn Voltage
25V Firing Voltage
300V.
Yes these readings are normal for the primary because the car runs good and there is no problems with the car. Dwell should be the same across all cylinders which it is. Firing voltage and burn time/voltage are good.
The parade pattern is good to know if the coil sparks weaker intermittently. It could help you for a intermittent missfire.
A stacked display can help diagnose because you can compare two waveforms.
Secondary Voltage Patterns.
Average firing voltage.
Average burn time.
The ignition voltages are normal because the car runs good.
Short sharp acceleration.
BURN TIME
Firing Voltage
All the above readings were at 5000RPM. The pattern are showing us this ignition system is in good condition.
Secondary Ignition Waveform.
Shorted Cylinder 4.Firing Voltage
1=4-6kV
2=4KV
3=6-7KV.
4=9KV.
Burn Time
1=0.6MS
2=1.3MS
3-1.2MS
4=1.3MS
Shorted Waveform
When it is shorted the voltage should increase and you can see by the above waveform. This shows the ignition system is good.Spark plug tester.
Cylinder 1. 5-7KV, 3.5ms Burn time
Cylinder 2. 4-6KV 0.8 ms Burn time
Cylinder 3 -2-3KV 1.4ms Burn Time
Cylinder 4 2-4KV 1.2MS burn time.
The spark plug tester was in plug one. the gap is larger in the tester so a higher voltage is produced. We could see a good spark.
WS4 Fuel Pressure and flow (Petrol only)
We located the fire extinguishers.
There was no leaks with the fuel pressure gauge plugged in.
The pressure with key on engine off was 0psi this is not right i don't think this gauge was very accurate.
Idling pressure 40psi.
Clamped return line 70PSI
WOT=50PSI.
Residual 41pSI.
It is important to check because if the fuel pressure is to high or low the car will be effected
negatively. it is only important to check if your car is having problems or you require more petrol by increasing the pressure.
Low fuel pressure means the car will run lean because there is less fuel being sprayed in the time the injectors are open.
Low fuel flow means the car will run lean from lack of petrol being pumped. This could be from a faulty pump.
High fuel pressure means the car will run rich because there is more fuel being sprayed in the time the injector is opened.
If the fuel pressure regulator was faulty this could mean rich or lean. If its seized open fuel pressure will be low and if its closed all the time pressure will be high.
There was no leaks with the fuel pressure gauge plugged in.
The pressure with key on engine off was 0psi this is not right i don't think this gauge was very accurate.
Idling pressure 40psi.
Clamped return line 70PSI
WOT=50PSI.
Residual 41pSI.
It is important to check because if the fuel pressure is to high or low the car will be effected
negatively. it is only important to check if your car is having problems or you require more petrol by increasing the pressure.
Low fuel pressure means the car will run lean because there is less fuel being sprayed in the time the injectors are open.
Low fuel flow means the car will run lean from lack of petrol being pumped. This could be from a faulty pump.
High fuel pressure means the car will run rich because there is more fuel being sprayed in the time the injector is opened.
If the fuel pressure regulator was faulty this could mean rich or lean. If its seized open fuel pressure will be low and if its closed all the time pressure will be high.
WS2 Flash Codes
Honda Integra DA6.
The procedure to extract the fault codes is. Jump the two wires in the connector. Turn ignition on the check engine light should be on and will flash the appropriate error code if there is a problem with the car.A long flash means 10 a short flash means 1
3 MAP Unplugged
6 ECT Unplugged
7 TPS Unplugged
The problems under the bonnet were the MAP, ECT and TPS were all unplugged.
We plugged all the connectors back in and the engine ran properly again.
To clear the codes we disconnected the battery.
There were no codes in the ECU any more.
The car wouldn't idle with the MAP, ECT and TPS unplugged.
The other tests you should do depends on what problem the car is having. Checking the fault codes will tell you the problem then you can replace or check the circuit that was displayed with a error code.
The procedure to extract the fault codes is. Jump the two wires in the connector. Turn ignition on the check engine light should be on and will flash the appropriate error code if there is a problem with the car.A long flash means 10 a short flash means 1
3 MAP Unplugged
6 ECT Unplugged
7 TPS Unplugged
The problems under the bonnet were the MAP, ECT and TPS were all unplugged.
We plugged all the connectors back in and the engine ran properly again.
To clear the codes we disconnected the battery.
There were no codes in the ECU any more.
The car wouldn't idle with the MAP, ECT and TPS unplugged.
The other tests you should do depends on what problem the car is having. Checking the fault codes will tell you the problem then you can replace or check the circuit that was displayed with a error code.
WS1 Petrol Fuel Injector Testing
All injectors sounded good and are working.
Voltage at injectors ignition on
Injector 1 =12V
Injector 2=12V
Injector 3=12V
Injector 4=12V
Test light
The light flashed on all injectors when wired in. The light flashed as the injector fires.
Duty Cycle
Injector 1 =98.7%
Injector 2=98.7%
Injector 3=98.7%
Injector 4=98.7%
Duty Cycle acceleration
Injector 1 =88%
Injector 2=90%
Injector 3=88%
Injector 4=90%
Hertz
Injector 1 =6.1hz
Injector 2=6.2hz
Injector 3=6.3hz
Injector 4=6.3hz
Hertz increased engine RPM
Injector 1 =18hz
Injector 2=20hz
Injector 3=18hz
Injector 4=20hz.
Calculated Pulse width modulation.
“Pulse width ms= (% Duty cycle x100)/Frequency"
Calculated Times at IDLE
Injector 1= 98.7x100/6.1=1618MS
Injector 2 =98.7x100/6.2=1591MS
Injector 3= 98.7x100/6.3hz=1566ms
Injector 4= 98.7x100/6.3hz1566ms
Calculated Times under acceleration
Injector 1=88x100/18=488MS
Injector 2=90x100/20=450MS
Injector 3=88x1o0/18=488MS
Injector 4=90x100/20=450MS
The above tests were acceptable to test injectors checking voltage to injectors was the most important test. If we had a problem with our car or injector not firing you would be able to hear it from the first test the injector would not click.
Voltage at injectors ignition on
Injector 1 =12V
Injector 2=12V
Injector 3=12V
Injector 4=12V
Test light
The light flashed on all injectors when wired in. The light flashed as the injector fires.
Duty Cycle
Injector 1 =98.7%
Injector 2=98.7%
Injector 3=98.7%
Injector 4=98.7%
Duty Cycle acceleration
Injector 1 =88%
Injector 2=90%
Injector 3=88%
Injector 4=90%
Hertz
Injector 1 =6.1hz
Injector 2=6.2hz
Injector 3=6.3hz
Injector 4=6.3hz
Hertz increased engine RPM
Injector 1 =18hz
Injector 2=20hz
Injector 3=18hz
Injector 4=20hz.
Calculated Pulse width modulation.
“Pulse width ms= (% Duty cycle x100)/Frequency"
Calculated Times at IDLE
Injector 1= 98.7x100/6.1=1618MS
Injector 2 =98.7x100/6.2=1591MS
Injector 3= 98.7x100/6.3hz=1566ms
Injector 4= 98.7x100/6.3hz1566ms
Calculated Times under acceleration
Injector 1=88x100/18=488MS
Injector 2=90x100/20=450MS
Injector 3=88x1o0/18=488MS
Injector 4=90x100/20=450MS
The above tests were acceptable to test injectors checking voltage to injectors was the most important test. If we had a problem with our car or injector not firing you would be able to hear it from the first test the injector would not click.
Wednesday, November 10, 2010
WS6 Oxygen Sensors on Vehicle
Nissan Skyline 2000 rb20de
The oxygen sensor is located in the exhaust. To detect oxygen in the exhaust. This oxygen sensor had 3 wires. This is a zirconia oxygen sensor.
Waveform at 2500RPM.
The voltage goes from 0.2V to 0.8V The average is 0.5V
This oxygen sensor changed 15 times within ten seconds.
The signal tells the ECU if the car is running rich or lean. The signal changes voltage because the car switches between running rich or lean depending on the engine condition/load. The signal flucuates.The signal is working correctly if it wasnt the voltage would stay the same unless the engine is actually running rich or lean. This would be the effect not the cause.
Waveform at IDLE
The voltage goes from 0.6V to 0.1V or even less. Average is 0.3V
This oxygen sensor changed 15 times within ten seconds.
The signal is working correctly if it wasnt the voltage would stay the same unless the engine is actually running rich or lean. This would be the effect not the cause.The signal tells the ECU if the car is running rich or lean. The signal changes voltage because the car switches between running rich or lean depending on the engine condition/load. The signal flucuates
Oxygen Sensor Rich.
It should go up to 1v or 0.9V when fully rich. This waveform shows 0.7V.
If this signal didnt go high normally this would indiciate it was running lean. It should flucuate between 0.1V and 0.9V. if it didnt go high, the voltage would always be low. This signal flucuates so it is working correctly.
oxygen lean
If the signal doesnt go low this means the car is running rich all the time. This signal flucuates so it is working correctly.
This oxygen sensor took 500ms to respond to the change.
How a Zirconia oxygen sensor works
Zirconium oxide ceramic along with a platinum coated electrode and a heater make up the major internal components of the zirconia oxygen sensor. The zirconia sensor generates its own voltage and is not reliant on the ECU to operate. The main element is the zirconia ceramic, which becomes conductive for oxygen ions at about 310° C. At this temperature, zirconia dioxide develops an electrical charge as oxygen ions pass through it. Since nature is constantly seeking to balance itself, when you place zirconia ceramic between environments with different amounts of oxygen, as the oxygen passes through the zirconia to offset the balance, the zirconia will develop a slight charge. The strength of that charge will depend on how many oxygen ions pass through it. The greater the difference in oxygen between the two atmospheres, the greater the charge developed. The zirconia oxygen sensor then uses a thin platinum coating to accumulate that charge, carry it to the sensor wires and onto the ECU.
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