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Results are grouped by useful content—not by paid placement or guessed parts. Describe the symptom naturally; IAR recognizes common alternate wording while keeping exact codes and vehicle details precise.
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The fuel system stores and meters fuel under controlled conditions. A no-start, lean code, odor, or hesitation can involve supply, command, air measurement, electrical control, mechanical condition, or vapor management.
System guideThe engine turns stored fuel energy into controlled torque. Good diagnosis separates a combustion problem from a mechanical, control, mounting, or support-system problem before parts are removed.
System guideThe control system reached a rich-condition diagnostic threshold for Bank 1. The data does not by itself prove an injector, fuel-pressure, MAF sensor, or oxygen-sensor failure.
Generic codeThe control system reached a rich-condition diagnostic threshold for Bank 2. The data does not by itself prove an injector, fuel-pressure, MAF sensor, or oxygen-sensor failure.
Generic codeThe control system reached a lean-condition diagnostic threshold for Bank 1. The data does not by itself prove a vacuum leak, MAF sensor, or fuel pump.
Generic codeThe control system reached a lean-condition diagnostic threshold for Bank 2. The data does not by itself prove a vacuum leak, MAF sensor, oxygen sensor, or fuel-delivery failure.
Generic codeThe control module detected a misfire pattern associated with cylinder 1. It does not identify the failed component.
Generic codeThe control module detected a misfire pattern associated with cylinder 2. It does not identify the failed component.
Generic codeThe control module detected a misfire pattern associated with cylinder 3. It does not identify the failed component.
Generic codeThe control module detected a misfire pattern associated with cylinder 4. It does not identify the failed component.
Generic codeThe control module detected a misfire pattern associated with cylinder 5. It does not identify the failed component.
Generic codeThe control module detected a misfire pattern associated with cylinder 6. It does not identify the failed component.
Generic codeThe control module detected a misfire pattern associated with cylinder 7. It does not identify the failed component.
Generic codeThe control module detected a misfire pattern associated with cylinder 8. It does not identify the failed component.
Generic codeThe generic EVAP monitor reported a system-level malfunction. The code identifies the monitored emissions system, not a failed cap, valve, hose, canister, sensor, or other specific part.
Generic codeThe generic EVAP monitor detected purge-flow behavior outside its expected strategy. The code does not prove the purge valve itself is failed; the flow path, sealing, sensing, electrical control, and vehicle-specific monitor conditions still have to be tested.
Generic codeThe EVAP monitor detected a small-leak or sealing condition. The code does not identify the physical leak location or prove which component failed.
Generic codeThe EVAP monitor detected a very small leak or inability to maintain the expected seal. The code does not identify the leak location or prove a specific valve, cap, hose, or canister failed.
Generic codeThe EVAP monitor detected a large-leak or inability-to-seal condition. It does not identify where the leak or control fault is located.
Generic codeThe engine did not reach the expected temperature behavior under the monitor’s conditions. The thermostat is one possibility, not the only one.
Generic codeThe control module detected intake-air-temperature sensor behavior outside its expected range or relationship. The code does not by itself prove the sensor, wiring, connector, intake condition, or control module is the cause.
Generic codeThe control module detected an intake-air-temperature sensor signal in a low range for its monitoring strategy. The code does not by itself prove the sensor, wiring, connector, intake condition, or control module is the cause.
Generic codeThe control module detected an intake-air-temperature sensor signal in a high range for its monitoring strategy. The code does not by itself prove the sensor, wiring, connector, intake condition, or control module is the cause.
Generic codeThe control module detected a malfunction in the mass-or-volume-air-flow circuit. The code does not by itself identify the sensor, wiring, intake path, power/ground, or control module as the cause.
Generic codeThe control module detected a mass-or-volume-air-flow circuit signal in a low range for its monitoring strategy. The code does not by itself prove a MAF sensor, wiring, connector, intake path, power/ground, or control module is the cause.
Generic codeThe control module detected a mass-or-volume-air-flow circuit signal in a high range for its monitoring strategy. The code does not by itself prove a MAF sensor, wiring, connector, intake path, power/ground, or control module is the cause.
Generic codeUse warning behavior, scan context, cylinder pattern, and controlled contribution evidence to separate ignition, fuel, air, and mechanical branches.
Test-first procedureSeparate missing ignition, fuel delivery, control, synchronization, and mechanical evidence after the engine is confirmed to crank.
Test-first procedureA fuel-economy complaint is meaningful only after establishing a repeatable baseline and separating normal operating changes from engine, emissions, tire, brake-drag, drivetrain, or temperature-control faults.
intermediateTreat gasoline or diesel odor as a safety signal first, then separate a liquid leak, vapor-system concern, refueling spill, exhaust odor, and cabin-source issue without running the vehicle beside an active leak.
professional recommendedUse the first starting split—cranks or does not crank—to choose the correct electrical, authorization, fuel, ignition, or mechanical diagnostic path.
beginnerUse operating conditions, code context, cylinder patterns, and targeted tests to separate ignition, fuel, air, mechanical, and control causes.
intermediateSeparate fuel, spark, compression, timing, and security-system faults with a test-first process.
IntermediateFirst determine whether the engine cannot make power, the transmission is not transferring it, or a chassis/control system is limiting torque.
intermediateClassify whether the engine stalls at idle, under load, during deceleration, immediately after starting, or with a broader electrical power loss before choosing a test path.
intermediateClassify smoke or a burning smell by location, color, timing, and nearby systems before attempting another drive or touching a hot component.
intermediateAn EVAP code identifies a monitored vapor-control condition, but the useful next test depends on whether the evidence points to a leak/sealing fault, purge-flow fault, electrical circuit fault, or an incomplete monitor.
intermediateIAR does not passively record this search. Save feedback only if you want a local note that you can export later for editorial planning. VIN-like vehicle identifiers are redacted before local save.