WS7 Exhaust Gas Analysis (Petrol only)
Make :: Toyota
Model:: 4A-FE
Exhaust Analyser should be warmed up and recently calibrated. When it’s time to start taking tailpipe readings, put the analyser probe into the tailpipe and install exhaust tube over probe to capture exhaust fumes. Make sure there is adequate ventilation
1. Below are the 4 gasses and what they are.
CO ...... means: Carbon monoxide.- this is a harmful gas to humans that is produced by the exhaust gassing in the car.Unburnt fuel that is carbon pushed out with the oxygen that goes in to the engine. .....................................................................................................................
HC ....... means: Hydrocarbon- if there is hydrocarbon coming out this is a indication of how lean or rich the car is running.
CO2 .....means: Carbon dioxide- carbon dioxide is made with the pressure of colourless gas pushed threw a carbon track, this gas can be found in a fizzy drinks therefore it is denser than air ,it is part of the burnt mixture in the combustion chamber.O2 ......means: Oxygen is the colourless air that enters threw the air intake port and helps burn the fuel in the combustion chamber, without this the car cannot work.
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Start the engine idling cold, and record the Four Gas readings Explain what is happening within the engine referring to the four gases:
- These results show that the carbon monoxide and hydrocarbons are very high. this is because of the cold start.
- These results prove that the engine is trying to run rich so it can worm it self up by addition of fuel and air..
When the engine has warmed up ,I record the Four Gas readings: in the graph below
- IN this reading first lambda shows that the engine is slightly running rich because the ECU is still adjusting to the changes.
- But the carbon monoxide has gone down witch shows that the engine has wormed up.
- in this car the engine is running slightly rich due being a old engine, this is why the lambda is staying slightly high.
:4. Run the warm engine at 2500 RPM, record the Four Gas readings: Explain what is happening within the engine referring to the four gases:
- At this point the Co has a massive increase in it, this is because the engine is burning fuel at a high level.
- All the other gasses are slightly gone up witch is ok for this type of RPM.
At idle, create a lean condition with an air leak or vacuum leak, record the Four Gas readings . Explain what is happening within the engine referring to the four gases.
- the Carbon oxide has inceased by 1%, this is a indication of the car being runiing richer than when its at 2500RPM.,the increase in HC is another condition of this condition.
- Carbon dioxide is gone slightly less because there is not much burnt oxygen coming out the exhaust.
- most there is a slightly high reading of un-burnt oxygen, this is why there is less co2
Disconnect one spark plug wire, ground it with a jumper wire, then record the
Four Gas readings as the engine idles:
Explain what is happening within the engine referring to the four gases:
- This experiment shows how us theer is un-burnt fuel in the conbustion chamber , witch is why it is producing more hydrocarbons.
With disconnected fuel injector shows that there is hardly any fuel in that chamber for the piston to fire back., in result there is less Co and less hydrocarbon than un-burnt fuel. ,there is more un-burnt oxygen as shownin the graph below..
Optional: Make other changes to the engine at idle, such as turning on the
air conditioning or rocking the steering wheel. Note the change you made:
Explain what is happening within the engine referring to the four gases:
- The car seemed to run ruff for a cupple of seconds then you could feel the ECU adjusting to the load in pressure and runs the engine richer.
- Because of reading all the voltage readings and referring back to the engine manuals and getting equipments like these to help us test the problems in these modern engines are efficiently.
- It is needed to have these in a engine for it to be economical as well as healthier for the ozone layer. as the human kind develops the way we travel evolves as well.
- ON lambda the 02 sensors the wire 1 is the white wire witch is the signal wire , the earth is body ground.
- 2nd wire is the heater wich is black and has a seprat wire for the ground,
- 3rd wire is a black wire also wich is a heater wire with a ground at body and signal wire.
