Frequently Asked Questions (FAQs)
1. What wires connect to the ignition coil?
The typical wiring for an ignition coil includes battery voltage power supply, ground, and a control circuit (trigger) from the PCM to a transistor circuit in the coil-on-plug assembly.
2. What are the 4 wires on ignition coil?
In a four-wire ignition coil setup, three wires are for power, chassis ground, and PCM command signal, similar to a three-wire coil. The fourth wire is a diagnostic circuit called 'IGF' and is connected in parallel with all the ignition coils. The PCM provides a 5-volt bias voltage on this circuit.
3. What are the symptoms of bad coil leads?
Signs of bad coil leads include an illuminated Check Engine Light, misfiring engine, hard starts, worsening gas mileage, diminished power, and sudden backfires.
4. Does it matter which way an ignition coil is wired?
The ignition coil will work efficiently and produce the same voltage regardless of how it is wired. However, the polarity of the spark plugs is more important, so it is crucial to ensure correct wiring for the spark plugs.
5. What color wire is the ignition wire?
The ignition wire is often colored pink or orange. It carries power from the ignition switch to the ignition coil and other components when the key is turned to the 'ON' or 'START' position. It energizes the engine's ignition system, allowing the engine to start.
6. Can ignition coil wires go bad?
Yes, ignition coil wires can go bad over time. Ignition coils are electrical components that can fail, just like any other electrical part. When they go bad, they may cause issues with starting the engine or result in misfires.
7. What happens if a coil is wired backwards?
If a coil is wired backwards, it can lead to decreased output by about 20%. This may not be noticeable at idle or low rpm, but under load and at higher engine rpm, it can cause the engine to misfire or stumble. To correct the polarity, the coil's primary leads need to be reversed.
