Lesson 1Engine coolant temperature and air intake temperature: impact on fueling and emissions control behaviorLearn how coolant and intake air heat affect fueling, timing, and emissions plans. Understand warm-up acts, sensor checks, and how wrong readings cause hard starts, smoke, or bad regeneration in Ghana's heat.
Cold start temperature expectationsECT vs IAT plausibility comparisonTemperature effects on injection timingImpact on EGR and DPF strategiesDetecting biased or stuck temp sensorsLesson 2Intake manifold pressure and ambient pressure: expected values at idle and under load, and relationships to boostStudy intake manifold and outside pressure data to check boost system work. Learn normal idle and load values, height effects, and use pressure links to spot boost leaks, stuck turbos, or wrong MAP sensors.
Ambient pressure and altitude effectsExpected MAP at key load pointsUsing KOEO readings for sensor checksPatterns indicating boost leaksDetecting MAP sensor bias or driftLesson 3Exhaust Back Pressure (or DPF differential pressure): expected ranges, regeneration triggers, and signs of restrictionLearn to read exhaust back pressure and DPF difference pressure PIDs. Know normal ranges at idle and load, how regeneration changes readings, and rising pressure shows exhaust blocks or bad DPF systems.
Normal back pressure at idle and loadDPF differential pressure thresholdsPressure behavior during regenerationIdentifying exhaust restrictions upstreamSensor and hose fault differentiationLesson 4Mass Air Flow (MAF) or Intake Air Mass: expected ranges, sensor response to throttle changes, and impact on fuelingLook at how to read MAF or air mass under different loads. Learn normal ranges, answer to throttle shifts, and how air flow works with EGR and boost to guide right fueling and smoke control diagnosis.
Baseline MAF at idle and no-loadMAF response to snap throttle testsMAF changes with EGR on and offUsing MAF to confirm boost deliveryDetecting contaminated MAF sensorsLesson 5Fuel rail pressure sensor voltage/PID and rail pressure demand vs actual comparisonUnderstand reading rail pressure sensor voltage and PIDs, and match ordered vs real values. Learn to spot slow answer, overshoot, and low pressure that shows pump, regulator, leak, or sensor troubles.
Typical rail pressure at idle and WOTSensor voltage to pressure relationshipCommanded vs actual pressure graphsDiagnosing slow pressure responseIdentifying leaks and relief valve issuesLesson 6EGR position and flow indicators: typical position ranges, response to commands, and symptoms of EGR faultsUnderstand reading EGR position and flow data, match ordered vs real values, and spot slow or stuck answers. Learn how EGR faults hit drive, emissions, and split EGR issues from boost or air problems.
Typical EGR position ranges by loadCommanded vs actual EGR correlationSymptoms of stuck-open EGR valvesSymptoms of stuck-closed EGR valvesUsing MAF and MAP to confirm EGR flowLesson 7Injector correction/individual cylinder trim: normal small trims, large corrections indicating injector/ECU/pressure issuesLearn how injector correction shows cylinder balance, fueling rightness, and burn quality. Know normal trim ranges, when big changes worry, and link patterns to mechanical, electrical, or ECU faults.
Normal trim ranges at idle and cruiseInterpreting positive vs negative trimsPatterns indicating faulty injectorsDistinguishing ECU vs mechanical issuesEffects of rail pressure errors on trimsLesson 8Engine RPM, throttle position, and accelerator pedal position: correlation checks and drive-by-wire sanityLook at how RPM, throttle spot, and pedal signals work in drive-by-wire setups. Learn to find match faults, dead areas, and delay that cause hesitation, limp mode, or unsafe speed in road tests.
Expected idle and cruise RPM valuesDual-track pedal sensor agreementThrottle plate vs pedal position trackingDetecting signal dropouts and noiseDrive-by-wire faults causing limp modeLesson 9Turbo boost pressure and wastegate control: expected boost curves, lag under load, and diagnosing boost leaksUnderstand turbo boost pressure and wastegate or VGT control data. Learn normal boost curves, okay lag, and use scan graphs to split boost leaks, sticking parts, and control issues from real engine load.
Target vs actual boost comparisonAcceptable turbo lag characteristicsUsing actuator command PIDsPatterns of boost leaks under loadOverboost and underboost fault cluesLesson 10Fuel temperature and fuel temperature sensor behavior: why it matters for fueling compensation and expected rangesLearn why fuel heat is watched, how it hits density and fixes, and normal ranges. Understand sensor acts during hot soak, recirculation, and how odd readings can trick rail pressure and amount control.
Normal fuel temperature operating rangeHot soak and recirculation effectsFuel temp influence on density modelsInteraction with rail pressure controlIdentifying faulty temp sensor signalsLesson 11High-pressure rail pressure: normal ranges, expected behaviors under load, and signs of low rail pressure issuesStudy high-pressure rail acts across running states. Learn normal pressure ranges, build-up times, and steadiness under load, and how changes point to worn pumps, injector leaks, valve faults, or supply side problems.
Pressure ramp-up during crankingStability at idle and steady cruisePressure response to rapid load stepsSigns of internal injector leakagePump wear vs suction restriction cluesLesson 12Battery voltage and crank/charge system parameters: effects on high-pressure pump and injector driver performanceUnderstand how battery voltage and charge data affect high-pressure pump output and injector drivers. Learn to check cranking voltage, alternator rule, and how low voltage can look like fuel or sensor faults.
Minimum cranking voltage thresholdsStarter current draw and RPM impactAlternator output and load responseVoltage sensitivity of injector driversLow-voltage induced false DTCs
