Lesson 1Engine coolant temperature an' air intake temperature: impact on fuelin' an' emissions control behaviorLearn how coolant an' intake air temperature dem influence fuelin', timin', an' emissions strategy dem. Understand warm-up behavior, sensor plausibility check dem, an' how incorrect readin' dem cause hard start dem, smoke, or poor regeneration control.
Cold start temperature expectation demECT vs IAT plausibility comparisonTemperature effect dem on injection timin'Impact on EGR an' DPF strategy demDetectin' biased or stuck temp sensor demLesson 2Intake manifold pressure an' ambient pressure: expected value dem at idle an' under load, an' relationship dem to boostStudy intake manifold an' ambient pressure data to verify boost system performance. Learn expected idle an' load value dem, altitude effect dem, an' how to use pressure relationship dem to detect boost leak dem, stuck turbo dem, or inaccurate MAP sensor dem.
Ambient pressure an' altitude effect demExpected MAP at key load point demUsin' KOEO readin' dem fi sensor check demPattern dem indicatin' boost leak demDetectin' MAP sensor bias or driftLesson 3Exhaust Back Pressure (or DPF differential pressure): expected range dem, regeneration trigger dem, an' sign dem of restrictionLearn how to interpret exhaust back pressure an' DPF differential pressure PID dem. Understand normal range dem at idle an' load, how regeneration affect readin' dem, an' how risin' pressure trend dem reveal exhaust restriction dem or failin' DPF system dem.
Normal back pressure at idle an' loadDPF differential pressure threshold demPressure behavior durin' regenerationIdentifyin' exhaust restriction dem upstreamSensor an' hose fault differentiationLesson 4Mass Air Flow (MAF) or Intake Air Mass: expected range dem, sensor response to throttle change dem, an' impact on fuelin'Explore how to interpret MAF or calculated air mass readin' dem under various load dem. Learn expected range dem, response to throttle change dem, an' how airflow data interact wid EGR an' boost to guide accurate fuelin' an' smoke control diagnosis.
Baseline MAF at idle an' no-loadMAF response to snap throttle test demMAF change dem wid EGR on an' offUsin' MAF to confirm boost deliveryDetectin' contaminated MAF sensor demLesson 5Fuel rail pressure sensor voltage/PID an' rail pressure demand vs actual comparisonUnderstand how to read rail pressure sensor voltage an' pressure PID dem, an' compare commanded versus actual value dem. Learn to recognize slow response, overshoot, an' low-pressure event dem dat indicate pump, regulator, leak, or sensor problem dem.
Typical rail pressure at idle an' WOTSensor voltage to pressure relationshipCommanded vs actual pressure graph demDiagnosin' slow pressure responseIdentifyin' leak dem an' relief valve issue demLesson 6EGR position an' flow indicator dem: typical position range dem, response to command dem, an' symptom dem of EGR fault demUnderstand how to read EGR position an' flow data, compare commanded versus actual value dem, an' recognize slow or stuck response dem. Learn how EGR fault dem affect drivability, emissions, an' how to separate EGR issue dem from boost or airflow problem dem.
Typical EGR position range dem by loadCommanded vs actual EGR correlationSymptom dem of stuck-open EGR valve demSymptom dem of stuck-closed EGR valve demUsin' MAF an' MAP to confirm EGR flowLesson 7Injector correction/individual cylinder trim: normal small trim dem, large correction dem indicatin' injector/ECU/pressure issue demLearn how injector correction value dem reflect cylinder balance, fuelin' accuracy, an' combustion quality. Understand normal trim range dem, when large deviation dem a concern, an' how to link pattern dem to mechanical, electrical, or ECU-related fault dem.
Normal trim range dem at idle an' cruiseInterpretin' positive vs negative trim demPattern dem indicatin' faulty injector demDistinguishin' ECU vs mechanical issue demEffect dem of rail pressure error dem on trim demLesson 8Engine RPM, throttle position, an' accelerator pedal position: correlation check dem an' drive-by-wire sanityExplore how RPM, throttle position, an' accelerator pedal signal dem interact in drive-by-wire system dem. Learn to spot correlation fault dem, dead spot dem, an' latency dat cause hesitation, limp mode, or unsafe acceleration behavior durin' road test dem.
Expected idle an' cruise RPM value demDual-track pedal sensor agreementThrottle plate vs pedal position trackin'Detectin' signal dropout dem an' noiseDrive-by-wire fault dem causin' limp modeLesson 9Turbo boost pressure an' wastegate control: expected boost curve dem, lag under load, an' diagnosin' boost leak demUnderstand turbo boost pressure an' wastegate or VGT control data. Learn expected boost curve dem, acceptable lag, an' how to use scan tool graph dem to separate boost leak dem, stickin' actuator dem, an' control issue dem from genuine engine load problem dem.
Target vs actual boost comparisonAcceptable turbo lag characteristic demUsin' actuator command PID demPattern dem of boost leak dem under loadOverboost an' underboost fault clue demLesson 10Fuel temperature an' fuel temperature sensor behavior: why it matter fi fuelin' compensation an' expected range demLearn why fuel temperature monitored, how it affect density an' compensation, an' what range dem typical. Understand sensor behavior durin' hot soak, recirculation, an' how abnormal readin' dem can mislead rail pressure an' quantity control.
Normal fuel temperature operatin' rangeHot soak an' recirculation effect demFuel temp influence on density model demInteraction wid rail pressure controlIdentifyin' faulty temp sensor signal demLesson 11High-pressure rail pressure: normal range dem, expected behavior dem under load, an' sign dem of low rail pressure issue demStudy high-pressure rail behavior across operatin' condition dem. Learn normal pressure range dem, ramp-up time dem, an' stability under load, an' how deviation dem point to worn pump dem, injector leakage, control valve fault dem, or supply side problem dem.
Pressure ramp-up durin' crankin'Stability at idle an' steady cruisePressure response to rapid load step demSign dem of internal injector leakagePump wear vs suction restriction clue demLesson 12Battery voltage an' crank/charge system parameter dem: effect dem on high-pressure pump an' injector driver performanceUnderstand how battery voltage an' chargin' data affect high-pressure pump output an' injector driver dem. Learn to evaluate crankin' voltage, alternator regulation, an' how low voltage can mimic fuel or sensor fault dem durin' diagnosis.
Minimum crankin' voltage threshold demStarter current draw an' RPM impactAlternator output an' load responseVoltage sensitivity of injector driver demLow-voltage induced false DTC dem
