lamba sonda kadett e cc 1.4

[ara]

kao ustanaoviti dali je ispravna lamba sonda?

[deki-ascona]

Re: lamba sonda kadett e cc 1.4

Ima gore opcija "pretraga" , pa ukucas sta te zanima. Uglavnom sve moze da se nadje.

Evo malo da se zanimas merenjem napona

Lamda sonda izbacuje napon od 0 do 1 volt i pokazuje 0.45 v kada je idealno sagorevanje . .

pozdrav

[Valent Vudriga]

Re: lamba sonda kadett e cc 1.4

Lamda sonda izbacuje napon od 0 do 1 volt i pokazuje 0.45 v kada je idealno sagorevanje . .

Pogresna informacija.

[deki-ascona]

Re: lamba sonda kadett e cc 1.4

Htedoh da ukazem na "pretragu", a plasirao sam losu informaciju

izvinjavam se, bolje da sam cutao...

[Valent Vudriga]

Re: lamba sonda kadett e cc 1.4

Chapter 8 - Diagnostic Procedures Performing Component Tests
Page 103
AirCare
Certified Emissions Repair Manual
Performing Component Tests
This section provides general information on the testing of
individual components that may cause excess emissions. Because
there can be many variations in components from vehicle to
vehicle, you should refer to the manufacturer’s recommended
procedures and specifications when performing tests.
O2 Sensor Testing
You should be in the habit of checking O2 sensor performance on
every vehicle you work on because of the importance of O2
sensors to controlling emissions, and the fact that it is very
common for O2 sensors to wear out and fail.
To accurately evaluate the performance of an O2 sensor, you must
determine the voltage range, response time and number of cross
counts. To do this you will need to perform at least two tests: a
snap-throttle test, and a cross-count test. Both use a digital
storage oscilloscope (DSO) to monitor voltage over time.
Snap-Throttle Test
This test provides you with measurements for four important
parameters respecting O2 sensor performance:
• maximum voltage
• minimum voltage
• response time from rich to lean
• response time from lean to rich
The test quickly forces the fuel system rich and lean while
recording the O2 sensor voltage. Because the DSO stores the
measurements, you don’t have to perform four tests to examine
four parameters. You perform the test and then observe four
different aspects of the waveform.
Table 3: O2 Sensor Performance Criteria
Test Specification
Maximum voltage when forced rich greater than 900 millivolts (mV)
Minimum voltage when forced lean less than 100 mV
Maximum response time
from lean to rich
less than 100 ms
between 300 mV and 600 mV
Maximum response time
from rich to lean
less than 100 ms
between 600 mV and 300 mV
Cross counts at 2500 rpm at least 5 cross counts in a
10 second period
Chapter 8 - Diagnostic Procedures Performing Component Tests
Page 104
AirCare
Certified Emissions Repair Manual
The O2 sensor response time is the amount of time that it takes
for the voltage to rise from 300 millivolts (mV) to over 600 mV, or
to drop from 600 mV to less than 300 mV. Response must be
checked in both directions to conclusively check an O2 sensor.
Performing The Snap Throttle Test
1) Locate the O2 sensor signal wire and connect the signal probe of
your DSO.
2) Connect the COM probe to the O2 sensor ground circuit or to the
engine block.
3) Start the engine and run at 2500 rpm for a couple minutes while
you adjust the DSO settings (see “DSO Setup For Measuring O2
Sensor Range and Response” on page 105). The DSO voltage
scale should be 200 mV per division and the time scale should
be 500 ms per division. Set the acquisition and trigger mode to
automatic/normal.
4) Quickly snap the throttle several times and press the button on
your DSO that freezes the waveform. Observe the waveform as
outlined below.
Reading Maximum O2S Voltage
Looking at the waveform on your DSO, you should see a voltage
spike (an increase and an accompanying decrease) for each time
you snapped the throttle. Identify and record the highest voltage
produced by the O2 sensor. A good O2 sensor will generate more
than 900 mV under such conditions.
Reading Minimum O2S Voltage
Looking at the waveform on your DSO, you should see a voltage
dip immediately following each snapped of the throttle. Identify
and record the lowest voltage produced by the O2 sensor. A good
O2 sensor will generate less than 100 mV under such conditions.
Measuring O2S response time
1) Note the 300 mV and 600 mV points on either an upslope or a
downslope of the O2 sensor waveform. If your DSO has measurement
cursors, set them at these points (see Figure 20 on
page 105). The distance from left to right between the two cursors
is the response time (see Figure 21 on page 105).
2) Measure this distance as precisely as possible using the cursor
read-out or zoom feature. Record this value (in milliseconds).
3) Repeat steps one and two for the other slope (up or down). It is
important to measure the O2 sensor’s response time from
300mV to 600 mV and from 600mV to 300mV.
You should see a response time of no more than 100 milliseconds
on a good O2 sensor. If not, perform the “More Conclusive O2
Sensor Response Time Test” on page 106 to verify response time
before condemning the sensor.
Chapter 8 - Diagnostic Procedures Performing Component Tests
Page 105
AirCare
Certified Emissions Repair Manual
Figure 20: DSO Setup For Measuring O2 Sensor Range and Response
Figure 21: Reading Response Time On DSO
The first
cursor is
placed at
600 mV.
The second
cursor is
placed at
300 mV.
DSO is set so that 0 volts is here
At 200 mV per division,
1 volt is here
y axis = voltage (200 mV per division)
x axis = time (100 ms per division)
y axis = voltage (200 mV per division)
x axis = time (100 ms per division)
dX: 28.5714 mS dY: 329.714 mV
X1: 182.143 mS Y1: 629.143 mV
X2: 210.714 mS Y2: 299.429 mV
dX = the distance
between the
cursors along the
X axis. In this
case 28.5714 mS.
Chapter 8 - Diagnostic Procedures Performing Component Tests
Page 106
AirCare
Certified Emissions Repair Manual
More Conclusive O2 Sensor Response Time Test
In most cases it won’t be necessary to do an additional test to
measure the O2 sensor response time. You can measure it using
the waveform captured in the snap throttle test. However, if it
appears that response time is not fast enough, perform the
following test to verify that the O2 sensor is defective before
condemning it.
Performing the Response Time Test
1) Locate the O2 sensor signal wire and connect the signal probe of
your DSO.
2) Connect the COM probe to the O2 sensor ground circuit or to the
engine block.
3) Locate a large manifold vacuum inlet and attach a propane
enrichment device.
4) Start the engine and run at 2500 rpm for a couple minutes while
you adjust the DSO settings. The DSO voltage scale should be
200 mV per division and the time scale should be 500 ms per
division. Set the acquisition and trigger mode to automatic/normal.
5) Let the engine idle. You must perform the next step within 30
seconds.
6) Slowly and steadily apply propane enrichment. The system
should compensate for the added propane by reducing the injector
pulse width (or leaning the mixture control solenoid duty if
carburetted). Continue to apply more and more propane enrichment.
Eventually (after about 20 seconds of adding propane) the
system will usually run out of range to compensate for the
added propane. Continue to add more propane and the engine
will start to run rough and rpm may drop. Do not stall the
engine.
7) Now that the engine is running extremely rich, quickly pull the
propane source hose off of the vacuum inlet to instantly create a
very lean mixture.
8) O2 sensor voltage should drop very rapidly (how rapidly is what
you want to measure). After the drop in O2 sensor voltage has
moved to the center of your DSO screen, press the button that
freezes the waveform.
9) Measure the time that it took for O2 sensor voltage to drop from
600mV to 300mV (see Figure 21 on page 105). A good O2 sensor
will take no more than 100 milliseconds.
Chapter 8 - Diagnostic Procedures Performing Component Tests
Page 107
AirCare
Certified Emissions Repair Manual
Cross Counts
Measurement of cross counts should only be made after 30
seconds with a warmed-up engine operating at 2500 rpm. This
should be adequate time for a normally functioning O2 sensor to
be fully functional.
Performing the Cross Count Test
While maintaining a 2500 rpm high idle, record the number of
times in a 10 second period that the O2 sensor voltage crosses the
mid-point of its range (450 millivolts). See Figure 22 on page 107.
Figure 22: O2 Sensor Cross Counts on DSO
Each upslope and downslope that crosses the mid-point should be
counted as one cross count. A minimum of 5 cross counts should
be evident in a 10 second period. This minimum applies to older
systems using throttle body injection or feedback carbs. Other
systems may have different minimum cross counts so you should
consult the manufacturer’s specifications.
Zirconia vs. Titania O2 Sensors
O2 sensors made with a zirconia ceramic are by far the most
common type. They generate a high voltage (1 volt) when the
exhaust is rich and a low voltage (0 volts) when the exhaust is
lean. Zirconia O2 sensors may have one, two, three, or four wires,
depending on whether a redundant ground circuit and/or a heater
is used.
y axis = voltage (200 mV per division)
x axis = time (100 ms per division)
DSO is set so that
0 volts is here
At 100 mV per division,
1 volt is here
Chapter 8 - Diagnostic Procedures Performing Component Tests
Page 108
AirCare
Certified Emissions Repair Manual
O2 sensors made with a titania ceramic can be found on some
vehicles manufactured by Chrysler/Jeep, Nissan, Toyota, and
Landrover. Titania O2 sensors are unique in operating principle
because, unlike the zirconia oxygen sensors, the titania sensors
are a variable resistor that works on a reference voltage and pulls
it down to ground. The reference voltage is usually 1 volt but on
some vehicles, the reference voltage is 5 volts (see note below).
Testing of titania O2 sensors (range, response time, and cross
counts) is usually the same as for zirconia sensors. The
specifications will usually be similar with the exception of voltage
range. For more information consult the manufacturer’s
specifications.
NOTE: Titania sensors in some vehicles (pre-1991 Jeep 4.0L for
example) use a 5-volt reference voltage and operate inversely to
normal. With these sensors, rich exhaust results in a low O2
sensor voltage.
Catalytic Converter Testing
Technicians and equipment manufacturers have tried and tried to
find a conclusive yet non-intrusive way of testing the performance
of a catalytic converter. A visual inspection is only useful in
detecting physical damage to the catalytic converter. Temperature
measurement may be useful in determining whether the cat is
completely dead, but you cannot accurately determine the
difference between 60% and 80% catalyst efficiency by measuring
temperature. In other words, it is inconclusive.
There is only one way to conclusively check the performance of a
catalytic converter—comparing gases sampled before and after the
converter.
For marginal IM240 failures you should evaluate catalytic
converter performance based on before and after testing in
conjunction with a review of the DTR and SBS report (see “Using
The DTR To Assist Your Diagnosis” on page 47 and “How The SBS
Readings Can Assist Your Diagnosis” on page 62). Remember that
the IM240 inspection procedure gives vehicles ample opportunity
to pass and a borderline fail is still a fail.
Before and After Sampling
The concept of catalyst performance testing is pretty simple when
you think about what the converter’s job is—to reduce the harmful
pollutants coming out the tailpipe. Determining how much they are
reduced will give you a valid measurement of performance or, in
this case, efficiency.
The arithmetic is pretty basic. The difference between engine-out
emissions (gases going into the catalyst) and tailpipe emissions