Lesson 1Visual inspection checklist: intake, vacuum lines, ignition, fuel system, sensorsThis lesson gives a step-by-step visual check routine before deeper tests. You'll inspect intake parts, vacuum hoses, ignition bits, fuel setup, and sensors you can see to spot clear problems fast and save time in the workshop.
Inspecting intake ducts and air filter boxChecking vacuum hoses and PCV routingReviewing coils, wires, and spark plugsLooking for fuel leaks and line damageSensor connector and harness inspectionLesson 2Repair planning: parts to consider (fuel filter/pump, injectors, ignition coils/plugs, MAF, intake gaskets), special tools, torque specs lookup strategyHere you'll learn to plan fixes after finding faults. List possible parts, check they fit, figure tools needed, and find torque values and steps to stop repeat visits and wasted effort in your garage.
Listing probable parts by systemChecking part numbers and compatibilityIdentifying needed special toolsFinding torque specs and sequencesPlanning workflow to reduce reworkLesson 3Interpreting diagnostic results: mapping symptom -> data pattern for common causes (vacuum leak, faulty O2/MAF, weak fuel pump, ignition fault, coolant/temp sensor)This teaches linking symptoms to data signs for root causes. Match fuel adjustments, O2, MAF, and misfire info to problems like air leaks, poor pumps, spark issues, or temp sensor faults common in local vehicles.
Recognizing vacuum leak data signaturesPatterns of weak fuel pump or restrictionIdentifying faulty O2 or MAF behaviorIgnition fault clues in misfire countersCoolant sensor errors and warm-up dataLesson 4Post-repair validation: warm-up behavior, fuel trim normalization, CEL verification, test drive acceptance criteriaLearn to verify fixes by watching warm-up, fuel trims, and engine light. Set test drive paths, pass standards, and record steps to make sure the issue is fully sorted for the customer.
Verifying cold and hot restart performanceMonitoring short and long term fuel trimsConfirming CEL status and code clearingDesigning a representative road test routeDefining pass or fail criteria and notesLesson 5Sensor and control component testing: MAF cleaning/check, intake vacuum/leak detection, EVAP leak test, cam/crank correlation checkCovers checks on main sensors affecting start, idle, fuel use. Clean and test MAF, find vacuum leaks, check EVAP, and verify cam-crank timing, vital for reliable repairs in Eritrean conditions.
MAF visual check, cleaning, and output reviewSmoke and propane tests for vacuum leaksEVAP leak test basics and common faultsCam and crank signal correlation checksInterpreting scan data from key sensorsLesson 6Basic bench and in-vehicle tests: fuel pressure, fuel rail leakdown, injector balance, compression test, cylinder misfire isolationEssential tests to split fuel, air, mechanical issues. Measure fuel pressure, leakdown, injector balance, compression, and find bad cylinders safely for precise fixes.
Static and running fuel pressure measurementFuel rail leakdown and regulator evaluationInjector balance and flow comparison methodsCompression and relative compression testingCylinder disable tests for misfire isolationLesson 7Customer communication script: plain-language explanation of findings, recommended repairs, risks of delay, maintenance advicePractice simple scripts to share findings and plans. Cover what's wrong, fixes, delay dangers, costs, and easy upkeep tips to gain customer trust in your shop.
Explaining fault codes in simple termsDescribing test results without jargonPresenting repair options and prioritiesDiscussing risks of delaying repairsGiving preventive maintenance guidanceLesson 8Cold-start and warm-up road test procedure and expected observationsStep-by-step cold start and warm-up drive test. Note RPM, idle, temp rise, fuel trims from start to warm for solid diagnosis.
Pre-start checks and ambient conditionsObserving initial crank and first idleMonitoring warm-up RPM and idle changesWatching coolant temp and closed loop entryRecording fuel trim trends during warm-upLesson 9Targeted customer intake questions for engine starting and idle issuesKey questions on conditions, fuel use, lights, past fixes, habits to guide quick, smart checks for start and idle woes.
Clarifying cold versus hot start conditionsQuestions on idle quality and stall eventsHistory of recent repairs and fuel qualityDriving patterns, trip length, and load useDocumenting warning lights and noisesLesson 10OBD-II scan strategy: reading freeze frame, pending/confirmed codes, live data PIDs to monitor (RPM, long/short fuel trims, O2, MAF, MAP, IAT, engine coolant temp)Step-by-step OBD scan plan. Read freeze data, codes, pick PIDs like RPM, trims, O2, MAF for sharp diagnosis.
Capturing and reading freeze frame dataSorting pending versus confirmed codesSelecting essential live data PIDsUsing fuel trims to narrow fault areasSaving and printing reports for recordsLesson 11Pre-drive and lift safety checks: battery, fuel leak, EVAP, cooling, mountsKey checks before drive or lift: battery, leaks, cooling, mounts to keep you, car, others safe.
Battery state, terminals, and cable securityFuel, EVAP, and exhaust leak inspectionCooling system level, leaks, and fan checkEngine and transmission mount conditionVerifying tire, brake, and steering basicsLesson 12Electrical and ignition tests: primary/secondary ignition checks, coil-on-plug testing, spark analysis with scope or substitute methodsTests for electrics and spark on hard start, rough idle. Check coils, spark with scopes or basics.
Primary ignition voltage and control checksSecondary ignition pattern interpretationCoil-on-plug resistance and output testsUsing scopes for spark and trigger signalsSubstitute tools when scopes are unavailableLesson 13Estimating labor and parts costs: time study approach, labor guides and parts sourcing checklistBuild quotes using time guides, checklists. Factor diag, rechecks, real prices for fair estimates.
Breaking jobs into estimate line itemsUsing labor guides and flat rate dataBuilding a parts and consumables checklistComparing OEM and aftermarket optionsIncluding diagnostic and recheck time
