A1 Engine Repair Practice Tests

A1 Engine Repair – What the Test Covers

The A1 test is engine mechanical diagnosis and repair — 45 scored questions in 75 minutes. Nearly half of it is diagnosis rather than teardown, so the exam leans hard on reading symptoms, running the right test, and knowing what that test can and cannot prove.

Content areas and their weighting below come straight from the 2026 Official ASE Study Guide task list. Every question on this site was written against one of these tasks, and the four tests in this subject are weighted to match.

Content Areas on the A1 Test:

• General Engine Diagnosis40% OF TEST
  18 questions — the largest area by a wide margin. Verifying the customer concern and road testing, researching service information and TSBs, separating a no-crank or hard-start from a non-engine cause, isolating noises and vibrations, diagnosing oil and coolant consumption and unusual exhaust color, manifold vacuum and pressure tests, cylinder power balance, cranking and running compression, cylinder leakage, PCV testing, and diagnosis with an oscilloscope, DMM or scan tool.
• Cylinder Head and Valve Train Diagnosis and Repair13% OF TEST
  6 questions. Head removal and inspection for cracks, warpage and corrosion, valves and seats, spring squareness and installed height, retainers and locks, stem seals, guide wear and stem-to-guide clearance, pushrods and rocker arms, valve lash and hydraulic lifters, camshaft drive components, journals and lobes, valve timing, head gasket and bolt torque procedure, and VVT and VVL components.
• Engine Block Diagnosis and Repair9% OF TEST
  4 questions. Engine removal and reinstallation, block inspection for cracks and warpage, piston oil cooling jets, cylinder wall and bore inspection, crankshaft end play and journal condition, reluctor ring inspection, main bearing wear patterns and clearances, camshaft bearings and alignment, auxiliary and balance shafts, piston and bearing wear patterns, connecting rods, the vibration damper, and flywheel and ring gear condition.
• Lubrication and Cooling Systems Diagnosis and Repair18% OF TEST
  8 questions — more than most people expect. Oil pressure and oil pump diagnosis, pan and gallery service, filters and coolers, coolant leaks and the cause of overheating, radiators, pressure caps, thermostats, water pumps, hoses and belts, fan operation including electric and clutch-driven fans, and coolant condition and service.
• Fuel, Electrical, Ignition, Air Induction and Exhaust Systems Diagnosis and Service20% OF TEST
  9 questions, and the area most often missed on what people think of as a mechanical test. Engine problems caused by faults in the fuel, air induction, electrical, ignition and exhaust systems, plus inspecting, testing and replacing components in each. A restricted exhaust and a weak fuel pump both arrive as a mechanical complaint, and this is where the exam checks whether you can tell the difference.