The ASE A8 Engine Performance test has 50 scored questions in five content areas, plus 10 unscored questions, and you get 75 minutes for all 60. Computerized engine controls is the biggest area at 13 questions (26.0%), then general diagnosis at 12 questions (24.0%). Fuel, air induction and exhaust has 9 questions (18.0%), and ignition and emissions controls have 8 each (16.0%). The emissions area splits further: 1 question on PCV, 2 on EGR, 2 on secondary air injection and the catalytic converter, and 3 on EVAP. Every question ties back to ASE's published task list. Questions are four-option multiple choice, including Technician A / Technician B items, trouble-code items, readings such as compression and vacuum, circuit diagrams and an EXCEPT item. A pass plus documented work experience certifies you for 5 years, and A8 is one of the eight tests for Master Automobile Technician.
01The test specification
The ASE test specification for ASE A8 Engine Performance splits the 50 scored questions across five content areas. ASE adds 10 unscored questions for research, and you have 75 minutes for all of them. Each area links to five free questions.
| Area | Content area | Scored questions |
|---|---|---|
| A | General Diagnosis | 12 (24%) |
| B | Ignition System Diagnosis and Repair | 8 (16%) |
| C | Fuel, Air Induction and Exhaust Systems Diagnosis and Repair | 9 (18%) |
| D | Emissions Control Systems Diagnosis and Repair | 8 (16%) |
| E | Computerized Engine Controls Diagnosis and Repair | 13 (26%) |
| Total | 50 |
02What is the ASE A8 Engine Performance test?
The ASE A8 Engine Performance test is one of ASE's certification tests for cars and light trucks. It covers driveability and emissions diagnosis: base engine testing, ignition, fuel, air induction and exhaust, emissions controls, and the computer that runs them, including OBD II.
It has 50 scored questions and 10 unscored ones, 60 in all, and you get 75 minutes. Every question is multiple choice with four options, (A) to (D). The unscored questions are there so ASE can gather statistics for future tests, and you cannot tell which ones they are, so treat every question as if it counts.
Passing is one half of certification. ASE also asks you to document relevant work experience, and its study guide says suitable vocational training can be credited toward it; the details are at workexp.ase.com. The study guide does not publish a passing score. Once certified, you hold the certification for 5 years, and you renew it with a shorter recertification test, which for A8 is 25 questions in 45 minutes.
A8 is one of the eight tests, A1 to A8, that ASE lists for recognition as a Master Automobile Technician. The full picture is in how Master Technician status works.
03What does each content area cover?
Area A: General Diagnosis (12 questions)
General diagnosis has 23 tasks, the most in A8. It starts like A1: confirm the complaint, research service information, find base engine mechanical faults, noise and vibration, and unusual exhaust color, smell or sound, then run vacuum or pressure, power balance, compression and leak-down tests and use a scope, engine analyzer or scan tool. It adds valve adjustment, cam timing (variable timing and lift included), driveability faults caused by the oil, operating temperature and cooling system checks, fans and active grille shutters, and reading schematics. The last group is electrical: driveability problems caused by the battery or by key-off drain, starting and charging faults, starter current draw, voltage drop tests on both circuits, alternator belts and pulleys, and the control wiring.
Area B: Ignition System Diagnosis and Repair (8 questions)
Seven tasks cover ignition. You diagnose ignition-related no-starts, hard starts, misfire, spark knock, power loss, poor mileage and emissions failures and find the root cause, interpret ignition codes, and test and repair the primary and secondary circuits, the coils, the ignition sensors, and the ignition or engine control module, including programming.
Area C: Fuel, Air Induction and Exhaust Systems Diagnosis and Repair (9 questions)
Fourteen tasks cover fuel, air and exhaust. The study guide adds a note: fuel injection questions can involve port injection, gasoline direct injection or both, on speed-density (MAP-based) or mass airflow systems, and the question names the type when it matters.
The tasks run from fuel-related symptoms (hot or cold no-starts, poor idle, wrong air/fuel ratio, hesitation, surging, stalling) through fuel trim and scan data, the tank, filler and cap, lines, the pump, its control circuit and filters, pressure regulation, fuel quality and pressure and volume testing, to the throttle body and its relearn, injectors, high-pressure lines and rails. Air induction covers filters, the intake manifold, variable runners, vacuum pumps, and vacuum leaks or unmetered air. Exhaust covers oxygen and air/fuel ratio sensors, catalytic converters and the rest of the system, restriction and leak tests, and turbochargers and superchargers.
Area D: Emissions Control Systems Diagnosis and Repair (8 questions)
This area is the only one in the build with sub-areas that carry their own question counts. PCV (1 question) covers driveability or emissions faults from the crankcase ventilation system and its filter, valve, oil separator and hoses. EGR (2 questions) covers EGR-related driveability faults, its scan data and codes, and its valve, passages, controls and coolers. Secondary air injection and the catalytic converter (2 questions) covers faults, scan data and codes, the air injection hardware and circuits, and tracing a catalyst code back to its root cause. EVAP (3 questions) covers faults, scan data and codes, and the canister, lines, filters and valves.
Area E: Computerized Engine Controls Diagnosis and Repair (13 questions)
Eleven tasks cover the engine computer and OBD II. You retrieve codes, monitor status and freeze frame data; research when a code sets and clears (permanent codes included) and how the malfunction lamp works; and diagnose driveability and emissions problems both with and without codes. You test sensors, actuators, circuits and the PCM with a scan tool, meter or scope, take voltage, voltage drop, current and resistance readings, and check power and ground distribution. The list also covers replacing and programming the PCM, problems caused by other systems (cruise control, security, traction and torque management, A/C, aftermarket accessories), network faults, and clearing codes and running the monitors to confirm the fix.
04What kind of questions are on it?
ASE's A8 study guide has ten sample questions drawing on several kinds of evidence. Some start from a trouble code and ask what could set it (a thermostat performance code, an EVAP small leak code, an EGR flow code). Some give you a reading: compression numbers before and after a wet test, or a vacuum gauge needle fluctuating at 2,000 rpm. Some show a circuit, such as a coil-on-plug ignition layout with lettered fault points.
Others are short reasoning chains: no spark and no injector pulse points to an input both systems share; fuel rail pressure above spec on a returnless system points to the part that regulates it. Learn which sensors and components each strategy depends on, so you can work backward from a combination of symptoms.
Three samples are Technician A / Technician B items, on a PCV test result, on wet compression results, and on blue exhaust smoke. See how to answer Technician A / B questions.
Reading traps
One A8 sample is an EXCEPT question, flagged by a warning line: three options could cause low EGR flow and one could not. In code questions, the code's exact wording matters: a code for flow that is too low and one for flow that is too high point to different causes.
05Where should your study time go?
Area E is 13 of the 50 scored questions (26.0%) and area A is 12 (24.0%): 25 of 50 (50.0%). Areas B, C and D share the other 25.
Area A has 23 tasks for 12 questions, so cover it for breadth; if you have studied for A1, its engine tests carry over. Area E has fewer tasks but more questions, and its content (OBD II rules, freeze frame, fuel trim, testing with and without codes) runs through the code questions in every other area too. In area D, the split tells you where to spend time: EVAP has 3 questions, PCV only 1.
Use the task list as a checklist and mark each task you could explain. ASE says every question represents one or more tasks. Pace: 60 questions in 75 minutes is about 1 minute 15 seconds each.
06Registering, retesting and recertifying
You register and pay through ase.com. ASE charges a $34 registration fee per order plus $62 for each test, so A8 on its own comes to $96. Each extra test in the same order adds $62, not another $96. ASE sets the registration and scheduling dates, so check ase.com for the current dates and fees before you book. The full breakdown is in ASE test fees and registration.
The test is delivered on screen. ASE offers a free demo of its testing platform at ase.com/free-test-drive, and the study guide notes two language aids: a Leer en español button that shows each question and its options side by side in Spanish and English, with no separate registration, and a Spanish/English pop-up glossary available during all ASE tests. More on the format: how ASE tests work.
If you do not pass, ASE makes you wait 30 days before you can take the test again. Spend the month on area E and on reading scan data, since code-based reasoning runs through most of the test.
After you pass, the certification runs for 5 years. To renew it you take the A8 recertification test, 25 questions in 45 minutes; you are eligible for it only after passing the full certification test once.
07Questions people ask
- How many questions are on the ASE A8 Engine Performance test?
- 60 questions in 75 minutes: 50 scored and 10 unscored. ASE uses the 10 unscored questions to gather statistics for future tests, and you cannot tell which ones they are, so answer all 60.
- What is the biggest content area on ASE A8?
- Computerized Engine Controls Diagnosis and Repair, with 13 of the 50 scored questions (26.0%), then General Diagnosis with 12. Fuel, air induction and exhaust has 9, and ignition and emissions controls have 8 each.
- What score do you need to pass ASE A8?
- ASE's study guide does not publish a passing score for A8. It publishes the content areas, the question counts and the task list. Check ase.com for how results are reported.
- How long does ASE A8 certification last?
- 5 years. To renew it you take the A8 recertification test, 25 questions in 45 minutes, which you can take only after passing the full A8 certification test once.
- How much does the ASE A8 test cost?
- ASE charges $62 per test plus a $34 registration fee per order, so A8 on its own is $96. A second test in the same order adds $62. Check ase.com before you book, since fees can change.
- Is ToolboxPrep affiliated with ASE?
- ToolboxPrep is an independent study site. It is not affiliated with or endorsed by ASE (the National Institute for Automotive Service Excellence). Our questions are original practice questions written to the published ASE test specifications; they are not actual test questions.
08Sources
- ASE Automobile Study Guide (Tests A1 to A9), 2026: the A8 test specification, question counts, testing time, the task list this page paraphrases, and the sample-question formats
- ASE (ase.com): the $34 registration fee per order, the $62 fee per test, the 5-year certification period and the 30-day retest wait
The content areas and question counts were checked against ASE's published study guide on October 11, 2026, and the task descriptions paraphrase its task list. ASE's study guide is the final word. If you find one of ours out of date, tell us.
Related: free practice questions · ten free A8 questions · how to answer Technician A / B questions · How ASE tests work
09Practice for this test
ToolboxPrep A8 practice tests are weighted to the specification above, area by area, and every answer is explained, all four options. You can try five sample questions with no account.
Ten free questions per test, no account: free practice questions. How our questions are written and checked: how our questions are made.
ToolboxPrep is an independent study site. It is not affiliated with or endorsed by ASE (the National Institute for Automotive Service Excellence). Our questions are original practice questions written to the published ASE test specifications; they are not actual test questions.