Bank 1 correction crossed the controller's lean threshold.
CASE 01Fuel controlIntermediate9 minutes
Lean at warm idle
2018 turbocharged gasoline sedan · MIL on; occasional rough warm idle
Simulated evidenceNo vehicle commandsEvery decision explained
THE FAILURE SCENE
The vehicle is fully warm and stationary. The scan is complete, the fuel-control state is closed loop, and no severe shaking or flashing MIL is present.
The fault matured at warm idle, not under road load.
The correction is strongest at idle and improves with airflow.
The captured controller supply does not show low voltage.
DECISION 1 / 3
What is the strongest first conclusion?
The pattern is repeatable across two warm-idle captures.
AUTHORSHIP · SOURCES · CORRECTIONS
See how this page earns trust.
These links are primary-source starting points for the page's scope. They do not replace the current manufacturer procedure, wiring, specification, or service information for a specific vehicle.
Publisher
ScanWrench Editorial is the working byline for this library. Joshua Black, founder and publisher, is responsible for publication decisions, disclosures, and corrections.
A reviewed date means an editorial scope and safety check. It is not an ASE credential, OEM authorization, or vehicle-specific repair approval.
Primary sources
- SAE J2012 — Diagnostic Trouble Code DefinitionsSAE International · Standardized DTC structure, definitions, and manufacturer-controlled ranges.
- SAE on-board diagnostics standards indexSAE International · Primary standards family for regulated OBD services, identifiers, and transport context.
- NHTSA datasets and APIsNational Highway Traffic Safety Administration · Primary U.S. recall, complaint, investigation, rating, and manufacturer-communication data.
Revision history
- Simulation review: claim boundaries, safety language, internal links, and cited source scope checked.
No material correction is hidden. Material additions and corrections are dated above when they occur.
Report a possible correction ↗