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TITLE PAGE.
INTORDUCTION TO WRITTEN COURSEWORK.
ENGINE MANAGEMENT AND MISFIRING.
29TH
OF JUNE 2015.
DR RAJ PERERA.
AKINWUMIJU BENJAMIN OLUWASEGUN STUDENT ID: 20277275
FD. MOTORSPORT TECHNOLOGY.

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ABSTARCT.
1.1 TITLE PAGE.
1.2 ABSRACT.
1.3 TABLE OF CONTENT.
1.4 INTRODUCTION.
1.5 MAIN BODY.
1.7 ENGINE MISFIRE CODES.
1.8 DIAGNOSTIC TEST.
1.9 CONCLUSION.
2.0 APPPENDICES.
2.3 REFFERENCES.

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TABLE OF CONTENT.
(1) INTRODUCTION. (Page 4).
(2) THE MAIN BODY. (Page 5 to Page 8).
(3) CONCLUSION. (Page 9).
(4) APPENDICES. (Page 10 to Page 12)
(5) REFFERENCENS. (Page 13).

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INTRODUCTION.
Engineering. This is the combination of science and mathematics that is used in the
real word for solving problems and improving the world. Basically thinking and
implementing ideas then translating it into real life is what distinguish engineering
from every other fields and mathematics. The term engineering was derived from a
Latin word, ingenium which means cleverness and ingeniare meaning to develop.
Engine misfire can be defined as the interruption of the air/fuel mixture in the
combustion chamber in any of the cylinders present in a car.

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MAIN BODY.
There are various areas in engineering, like civil engineering, chemical engineering,
electrical engineering, mechanical engineering, systems engineering and so on. The
particular area of engineering that I find interesting is the Mechanical engineering, I
love working on cars, finding faults on the engine misfiring and fixing it up. The
reason while I have interest in this is that driving happens to be one of my hubbies
and I also have flares for cars so in order not to limit myself to that alone, after
finishing my first degree in another area that differs from mechanical, I decided to go
back into an automobile industry for another four years where I learnt how to
diagnose, detect and fix up mechanical and engine management faults on cars of
various types. As a result of the experienced have gained I was awarded the
certificate of competency from various body as far as automobile is concerned. Due
to the love I have in working on cars I decided to take my destiny in my hands by
choosing this aspect of engineering as a career.
When it comes to finding faults on cars, this could be done with the use of some
diagnostic devices like the lunch box MXP431, A Snap-On diagnostics tool, Maxis
systemMS908 and the likes. Every electrical system on the car has a code and the
codes represents each sensors on the car, what the sensor does is that they help in
sending information to the ECU (Engine Control Module) whenever there is a fault.
The sensors can also give information about how the system functions. Most times
one does not need to use the diagnostic tool before one can actually analyse faults
on cars due to the professional experience acquired. If you know what every bit of all
the materials on cars is, what each of them does both electrical and non-electrical
materials, 70 percent of the problem is solved, with this one can go straight then get
it fix, rather than going about and not knowing what exactly the fault is.
Finding faults on car engines as really helped in engineering by monitoring a system,
recognise when there is a fault and telling what exactly the fault is and where the
fault is located. The faults can be analysed if the sensor has stopped working or the
values of data the sensor was supposed to be producing is lesser than the expected
value. Faults finding is done in the industry by keeping the records of the car since
the day there is a fault on such a car, what brought about the fault, the particular time
the fault was noticed. This will help a lot since such records is been taken on cars,
then it will even make the job more easier to do by going into the actual area where
the fault is and get it done, this will also help to know more about the after effect of
other systems on the cars and how long they will last so as to tell how soonest they
will need to be replaced.
Practices and methods like this are to be used in various industries and giving
training programmes to local mechanics on vehicle maintenance practices and
procedures in various countries such as vehicle repair and maintenance and
equipment tools, the use of engineering drawing, use of computer system for
vehicles faults diagnosis and repair, also the training of mechanics would help.

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Like we have in most general cars now a days, the vehicles are fitted with complex
electronic equipment like the traction control, immobilisers, power steering, airbags,
and so on, whenever any of this is faulty the light will be on and it is best to check on
this with an experienced professional. With the help of a professional and complex
device the fault would be identified and resolved. Diagnostic Equipment’s is one of
the essential tools that are needed for modern vehicle repairs. No matter what the
fault is on the car one of the machines will access the car and get the job done either
by clearing the fault memory or help in configuring the replaced. Equipment’s varies
from basic OBD scanners to the full dealer lever kits. On most of the full kits, an
update is required on the software thereby keeping up to date the latest changes on
the software.
Engine misfiring like I mentioned earlier at the beginning of this report engine misfire
is a common problem that occurs to cars that can sometime give the car much
problem thereby making it difficult to drive. The engine may shake badly when in a
potential position and cause a lot of vibration on the car, with this same fault the
engine may find it so difficult to start up, this performance will make the car to suffer
along with fuel economy and the emission quality will so bad even to the extent that
if the car should run an emission test the car is definitely going to fail due to high
level of hydrocarbons in the exhaust system.
Engine Misfire Code. Take for instance a four cylinder car, when one of the plugs is
misfiring is like 25% out of the out the 100% the engine needed is been lost. When
there is a serious misfire on a car the engine management light comes up or flashes,
the fault can be detected by plugging a diagnostic tool into the vehicle scan
connector located rightly under the dash board near the steering column. When
diagnosing a misfire code on cars, the last two codes will notify the cylinder number
that is misfiring, that is the digit represent the cylinder number of the engines firing
order.

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As shown on the table below.
P0300 RANDOM MISFIRE CODE MULTIPLE CYLINDER INVOLVED
P0301 CYLINDER 1 MISFIRE DETECTED
P0302 CYLINDER 2 MISFIRE DETECTED
P0303 CYLINDER 3 MISFIRE DETECTED
P0304 CYLINDER 4 MISFIRE DETECTED
P0305 CYLINDER 5 MISFIRE DETECTED
P0306 CYLINDER 6 MISFIRE DETECTED
P0307 CYLINDER 7 MISFIRE DETECTED
P0308 CYLINDER 8 MISFIRE DETECTED
P0309 CYLINDER 9 MISFIRE DETECTED
P0310 CYLINDER 10 MISFIRE DETECTED
P0311 CYLINDER 11 MISFIRE DETECTED
P0312 CYLINDER 12 MISFIRE DETECTED
Whenever the engine misfires, one of the following is likely to be the cause of it, (1)
The air and fuel mixture is too far from each other thereby making it too far to ignite
this can be as a result of dirty or bad fuel injector, low fuel pressure due to weak
pump and air leakages which could be from the EGR Valve, the P0401 Diagnostic
trouble code represent EGR CODE. (2) Loss of spark. That is the rate at which the
spark is to come through to the spark plugs. This could either be bad spark plug or
when the distributor cap is broken, excessive rotor gas inside the distributor. This will
affect the whole cylinders. (3) Loss of compression. When the engine loses
compression it means that the cylinder loses most of the air/fuel mixture before it can
be ignited. The likely causes of compression loss are burned exhaust valve, or when
the head gasket is burnt thereby causing leakages.
Whenever diagnosis is been carried out on cars, the diagnostic tool will help in
finding the code but the code cannot tell the reason for the misfiring. Which could be
ignition, compression or fuel related issue. Sometimes when a code like P0304
misfire code for cylinder number 4 and another code like P0200 which has to do with
injectors, one would know the misfire is likely caused by the injector on cylinder
number 4. And if there are codes like P0401 which is related to the EGR, this could
be as a result of carbon build up under the EGR valve. And whenever there is a lean
code like The P0171 or P0174, this means there could be a problem with the fuel
injector. And whenever there is a random multiple misfire this means the misfire is
random and moving around from one cylinder to another cylinder which will affect the
engine so much.

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DIAGNOSTIC TEST.
Whenever the engine misfires and there is no code coming up from any of the
cylinders even when tested with a diagnostic scanning tool. A professional grade
scan tool that can access MODE $06 DATA will be the appropriate tool to be used in
scanning the car and this will give you the misfire data that is being tabulated for
each cylinder. Normally the misfire reading on this should be at zero or close to zero
for every cylinder, but the OBD II SCANNER will not give a misfire code until when
the actual misfire count as gone up to about 2% for any cylinder. With the use of
MODE $06 DATA one will be able to know if any of the cylinders is at a high
abnormal rate.
Apart from diagnosing the car with use of diagnostic tools some test could also be
carried out to know what precisely the fault on the car is while it is misfiring. For
example; (1) diagnostic with a digital storage oscilloscope, this will help in detecting
the firing voltages for each of the cylinders. Starting from number one cylinder, then
to the next which is two and so on. If the voltage is lower or higher than the other one
it means there is fault on it. And if there almost the same a snap-KV test will help in
figuring out the fault. (2) Ignition and Compression test. To check this, once you
remove the spark plug if the misfire is from one plug this will be obvious and you will
know which of the plugs is causing the misfire. If the plug is okay check the insulator
to see if there is a crack or breakage on it. If no measure the plug wire resistance
end to end with the use of an ohmmeter. Check on the vehicles manufacturers’
specification, but ideally the resistance should not be more 8,000 ohms per foot.
(3) Leak-down test or Compression test. This will help to determine if the oil in the
engine is getting pass the valve or the rings. If you notice any trace of little leak-down
or good compression while little oil still escapes, (wet compression test). This will tell
if the engine needs a new valve guide or seals. (4) Fuel injection Test. One can start
with the checking for the voltage of the Injector, then the injectors should produce a
tinkle sound so as to be sure voltage is getting there. And if the voltage is getting
there and the injector is supplying low amount of fuel the air/fuel mixture will be less
thereby making the engine to misfire and this could be as result of dirt. And if the
injector is not producing any tinkling sound and you have checked on the socket that
supplies voltage and there is current it mean that the injector is dead and is not able
to supply fuel.

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CONCLUSION.
Whenever the engine misfires, one of the following is likely to be the cause of it, (1)
The air and fuel mixture is too far from each other thereby making it too far to ignite
this can be as a result of dirty or bad fuel injector, low fuel pressure due to weak
pump and air leakages which could be from the EGR Valve, the P0401 Diagnostic
trouble code represent EGR CODE. (2) Loss of spark. That is the rate at which the
spark is to come through to the spark plugs. This could either be bad spark plug or
when the distributor cap is broken, excessive rotor gas inside the distributor. This will
affect the whole cylinders. (3) Loss of compression. When the engine loses
compression it means that the cylinder loses most of the air/fuel mixture before it can
be ignited. The likely causes of compression loss are burned exhaust valve, or when
the head gasket is burnt thereby causing leakages.

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APPENDICES.

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REFFERENCES.
(1) Car Services, Repairs & MOT Stockport – John Delany Motors. 2015. Cars
Servicing, Repairs & MOT STOCKPORT – John Delany Motors. [ONLINE]
Available at: http://www.delany-motots.co.uk. [Accessed 02 July 2015].
(2) Engine Misfire | Fix it yourself! 2015. Engine Misfire | Fix it yourself! [ONLINE]
Available at: http://www.engine-misfire.com. [Accessed 02 July 2015].