How to Tell if You Have a Faulty Coil Pac
How a Coil Pack Works
When creating a spark at the spark plug, the fire must initiate from a high voltage supply, so as much fuel as possible burns in the cylinder. Whenever the combustion process is started, the coil pack builds up the energy, as much as 50,000 to 75,000 Volts. When the electronic control module (the car computer) sends the signal to the ignition control, the voltage is released from the coil pack through the spark plug cables to the spark plug.
When the spark travels to the spark plug, it jumps from the spark plug gap to the ground, causing an explosion of the fuel air mixture inside the cylinder chamber
Coil Pack Problems
Usually, if a coil pack is bad, there will be a loss of fire or spark in one or more cylinders. This causes what's commonly referred to as misfiring. Misfiring can cause drag on the crankshaft, and usually results in a very poor performing engine
Common Symptoms of a Faulty Coil Pack
A faulty coil pack will generally have symptoms similar to a faulty spark plug. Some of the most common tell tale signs that a coil may be defective include:
- A rough idle
- An unexplainably louder-than-usual engine
- A noticeable lack of power
- A significant drop in RPMs while accelerating for no apparent reason
- A blinking or intermittently activating check engine light
- An active gas warning light when the vehicle has plenty of gasoline
- Smoke from the exhaust emitting intermittently, instead of in a steady strea
How to Test a Coil Pack
Fortunately, there is an easy way to test the coil packs in your vehicle and make sure they're working as they should. You need to use ohm meter to test the coil pack for continuity. Make sure you have the approximate ohm values for the coil pack. To find this information, research your car's engine on the Internet or purchase a Chilton's or Haynes manual to find out what the mega ohms reading on the coil pack should be.
What Coil Pack Works with a Rotary Engine?
Most rotary engines require a different type of ignition coil pack. Below are two, one for a standard replacement, and one that is a higher voltage performance type coil pack.
Original Equipment Replacement
Beck Arnley is a well known name in the automotive ignition parts industry. They are favored by many mechanics, especially those that work mostly on import cars. The Beck Arnley 178-8025 rotary engine coil pack is a direct replacement for original equipment parts on older Mazda cars with a rotary engine. You can expect to pay about $55 for one.Performance Replacement
M&W Ignition Systems is a fairly well known name in the import performance market. Their part number PAK005 is a high performance ignition coil pack for the performance enthusiast who isn't afraid to spend a little more on a high quality high performance part. With prices running around $245 for a double coil pack for direct fire ignitions, these coil packs will deliver years of excellent performance.
When ordering a coil pack for your rotary engine equipped car, you need to know the year and model as well as the engine displacement to ensure you are given the correct parts.