Diagnostic Worksheet
There are many operating conditions that lead to the malfunction
of engine components. A good grasp of such conditions can make
troubleshooting faster and more accurate.
In general, each customer feels differently about a problem. It is
important to fully understand the symptoms or conditions for a
customer complaint.
Utilize a diagnostic worksheet like the one shown below in order to
organize all the information for troubleshooting.
WORKSHEET SAMPLE
Customer name MR/MS Model & Year VIN
Engine # Trans. Mileage
Incident Date Manuf. Date In Service Date
SymptomshStartabilityhImpossible to starthNo combustionhPartial combustion
hPartial combustion when engine is warm
hPartial combustion when engine is cool
hPossible but hard to starthOthers [ ]
hIdlinghNo fast idlehUnstablehHigh idlehLow idle
hOthers [ ]
hDriveabilityhStumblehSurgehKnockhLack of power
hOthers [ ]
hEngine stallhAt the time of starthWhile idling
hWhile acceleratinghWhile decelerating
hJust after stoppinghWhile loading
Incident occurrencehJust after deliveryhRecently
hIn the morninghAt nighthIn the daytime
FrequencyhAll the timehUnder certain conditionshSometimes
Weather conditionshNot affected
WeatherhFinehRaininghSnowinghOthers [ ]
TemperaturehHothWarmhCoolhColdhHumid ÉF
Engine conditionshColdhDuring warm-uphAfter warm-up
Engine speed
Road conditionshIn townhIn suburbshHighwayhOff road (up/down)
Driving conditionshNot affected
hAt startinghWhile idlinghAt racing
hWhile acceleratinghWhile cruising
hWhile deceleratinghWhile turning (RH/LH)
Vehicle speed
Malfunction indicator lamphTurned onhNot turned on
SEF907L
TROUBLE DIAGNOSIS Ð Introduction
EC-43
