Credential type: certification examination · verified on the issuer's site September 19, 2026 issuer page

Exam Domains

A General Powertrain Diagnosis 12%

B Computerized Powertrain Controls Diagnosis (including OBD II) 32%

C Ignition System Diagnosis 12%

D Fuel Systems and Air Induction Systems Diagnosis 16%

E Emission Control Systems Diagnosis 16%

F I/M Failure Diagnosis 12%

Exam Details

Question TypesMultiple Choice, Composite Vehicle Scenario (L-series)

FormatLinear (computer-based)

Online ProctoringAvailable

ID RequirementsOne government-issued photo ID with full name. Name must match ASE registration exactly.

RenewalRequired -- ASE certifications are valid for 5 years. Recertification is achieved by retaking and passing the current version of the test before the expiration date. No continuing education requirement — recertification is exam-only.

PrerequisitesCurrent ASE A8 Engine Performance certification required; 2 years of hands-on automotive technician experience

Retake Policy30-day waiting period between attempts. Full test fee required for retake. ASE registration fee applies per testing window.

LanguagesEnglish

L1 Advanced Engine Performance Specialist (L1) Exam Blueprint

Exam Domains

Exam Details

Official Study Resources