There is a special tool to grip the spark plug wire leads/caps to pull them off the plugs and (usually) not damage the wire. The tool looks like a pair of pliers with rubber coated jaws shaped to grip the plug wire lead/cap connected to the spark plug. Take the pliers and grip the plug wire lead/cap firmly, then twist and pull on the tool at the same time to remove from the plug (don't pull on the plug wire itself). When installing the plug wire lead/cap onto the plug use a bit of dielectric grease on the plug wire leads/caps to prevent rust/corrosion and the plug wires should be real easy to remove next time.
Vacuum leaks can be found using a tool called the Mighty Vac. The Mighty Vac connects to your vacuum system and then you create your own vacuum to check for leaks in the various vacuum system's sub-systems. Once you find the sub-system where the leak is, then you check the various components (lines, connections, valves, etc.) until you find the leak. Very useful tool since you can check for leaks in areas where a line or part is buried in a panel or other hard to reach place that other tools may not reach (like a stethoscope). You can also check your engine's condition, bleed brakes/master cylinders, remove fluid from hard to reach places, etc., etc.
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1977 300D: 300,000+ miles
American Honda: Factory Trained Technician & Honor Grad.
Technical Advisor to Am. Honda;
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