- 1). Remove all of the engine's spark plugs with a deep-set socket wrench.
- 2). Block the throttle wide open or have an assistant push the accelerator pedal to the floor.
- 3). Attach a compression gauge to a spark plug opening on the cylinder head. Note that the hose that protrudes from the bottom of the compression gauge has a threaded metal fitting on its tip. Turn that fitting in a clockwise direction into the spark plug opening until hand-tight.
- 4). Crank the engine to record the maximum gauge reading, then record that reading.
- 5). Repeat for the remaining cylinders.
- 6). Compare the recorded results. If the compression reading on two or more adjoining cylinders is much lower than the remaining cylinders, the head gasket is blown.
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