ASE L1: Advanced Engine Performance Specialist Certification Exam Practice Test
Build your confidence for ASE L1: Advanced Engine Performance Specialist Certification Exam. Practice the concepts, understand the answers, and strengthen your knowledge one question at a time.
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ASE L1 advanced certification for diagnosing complex driveability problems, emissions failures, and OBD II systems using advanced diagnostic techniques. Administered by ASE as a computer-based multiple choice using ase composite vehicle reference format exam. Key domains include Computerized Powertrain Controls Diagnosis (including OBD II), Emission Control Systems Diagnosis, Fuel Systems and Air Induction Systems Diagnosis and General Powertrain Diagnosis. The exam consists of 50 questions over 75 minutes.
Sample Questions
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A technician is identifying OBD II code families. Data available: DTCs displayed: P0442, P0455, P0456, P0457 What do these codes most directly share?
A sedan has a low-power complaint after a used engine installation. No misfire DTCs are present. Data available: MAP at hot idle is 54 kPa; calculated load is high at idle; vacuum gauge is low but steady; both banks LTFT are -8 percent; exhaust backpressure is normal Which test should be performed next?
A P0401 sets on a vehicle using MAP-based EGR diagnostics. Data available: commanded EGR causes MAP change below expected; EGR valve position PID follows command; intake passage inspection shows carbon restriction near one runner What is the best repair?
A car fails tailpipe CO after oxygen sensor replacement. Data available: upstream O2 switches; fuel trims remain -22 percent; MAF reads 11 g/s at hot idle on a 2.0L engine; unplugging MAF makes trims approach zero using substitute strategy What is the best next step?
A vehicle sets P0442 small leak. Data available: fuel tank pressure sensor changes with a hand vacuum pump; purge seals; vent valve command closes but smoke exits the vent filter area until the vent valve connector is repaired What caused the failed leak test?
Career Opportunities & Salary
Exam insights and study advice
In the real world, vehicles are increasingly complex networks of computers and sensors. A technician certified in L1 can systematically diagnose elusive problems-like a random misfire caused by a network glitch or a persistent check engine light tied to a failing catalyst monitor-saving hours of misdirected labor and unnecessary part replacement. This directly translates to higher shop profitability, increased customer trust, and the ability to correctly repair vehicles to meet stringent emissions standards. It moves practice from guesswork to precision.
Recommended
These are the backgrounds the certifying body suggests. Check the vendor's own page for anything it formally requires.
What this exam covers
Use the published domain weights to plan your study. Practice results do not predict your certification exam score.