What is a basic compression test procedure?

• A. Disable ignition, remove a spark plug, attach a compression gauge, crank the engine, and compare all cylinders to within spec; low readings indicate valve, piston, or ring issues.
• B. Disable ignition and remove the battery, then crank the engine.
• C. Check the coolant level and radiator pressure before testing.
• D. Use a timing light to measure compression.

Answer: (A)