How can you tell if a spark plug is a problem?
One plug wire with a resistance that’s significantly different than the other wires could indicate that’s the problem wire. When installing new wires, make sure you’re using wires specified for your vehicle.
Where is the coil wire on a spark plug?
Locate the negative coil wire. On most cars made before 1980, this wire connects to the points switch, which is located on the distributor. The distributor connects all of the spark plug wires.
Where does the blue wire go in a plug?
Inside the plug are three terminals: Neutral : The blue wire connects to the neutral terminal on the left of the plug. 1. Once you have cut the cables to the right length, and removed the insulation, twist the end of each cable. This ensures that there are no loose copper wires.
Where is the points switch on a spark plug?
On most cars made before 1980, this wire connects to the points switch, which is located on the distributor. The distributor connects all of the spark plug wires. Most newer cars do not have a points switch, so that terminal is connected to ground or the negative terminal of the battery.
How do you know which spark plug wire goes where?
It is the same as the firing order of the engine. This answers how do you know which spark plug wire goes where. An easier method to do this is to replace the spark plug wires, one at a time. Pull the old one from the spark plug and the distribution cap and replace it with a new one.
What should I do if my spark plug wire is bad?
With the engine running, move the test light along the length of each spark plug wire. If a spark jumps from a plug wire to the test light at any point, this is an indication that the insulation has broken down, and the spark plug wire should be replaced.
What are the symptoms of bad spark wires?
The most common symptom of bad spark plug wires is a rough engine idle. Spark plug wires are responsible for transmitting the electrical current from a vehicle’s electrical system to the engine spark plugs, where the electrical current is used to ignite the engine air/fuel mixture.
When to replace a spark plug in a car?
If you are certain it is not a battery issue, then you should replace the spark plug as soon as possible. Engine misfiring is one of the known symptoms of a bad spark plug wire in a car. This usually occurs when there is incomplete engine combustion. Engine misfires, because the cylinders are not working or firing fine.