- 1). Turn the ignition key to the "II" position. You should hear a slight two-second hum. This is the fuel pump and relay energizing. If you don't hear any hum, your fuel pump is not energizing and pressuring the fuel system. You'll need to have the fuel system serviced and the pump and relay replaced.
- 2). Open the hood and pull the vacuum hose off of the intake manifold (on the back side of the engine) with your hands and connect the vacuum pressure gauge to the vacuum hose.
- 3). Start the engine. Your vacuum pressure should stay steady at 20 to 22 PSI (pounds per square inch). If it doesn't, then you have a vacuum leak and a compression problem. You'll need to have the engine serviced by a professional mechanic.
- 4). Pull the spark plug wires off of the top of the engine with your hands. Only check one spark plug wire at a time. Lower the spark plug socket connected to the socket extension into the plug well. Turn the spark plug counterclockwise with the socket wrench to loosen and remove it. The spark plug socket contains a rubber interior that will grab onto the spark plug end, allowing you to pull it up and out of the engine.
- 5). Pull the spark plug out of the end of the socket and push it into the end of the spark plug wire you just removed. Make sure the electrodes of the plug are facing outwards.
- 6). Crank the engine and have an assistant check the spark plug for a blue spark jumping the plug's electrodes. Pull the spark plug out of the plug wires, and insert a small metal screwdriver into the end of the spark plug wire. Then, lay the plug wire and screwdriver down on the valve cover next to one of the mounting screws. Crank the engine again and check for a blue spark. If there is spark, your spark plugs have failed and need to be replaced. If there is no spark, then pull that plug wire off of the distributor side of the plug wire. Lay the metal tip of the screwdriver next to, but not touching, the electrode on the distributor. Crank the engine again. If there is no blue spark, then your power distributor has failed and needs to be replaced. If there is spark, then your plug wires have failed and need to be replaced.
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