How do you know when your ignition coil needs to be replaced?
Are you experiencing a noticeable lack of power when trying to accelerate...almost as if one of your cylinders isn't firing, or if all were just clunking along? Getting lower than average gas mileage? Is your engine stalling for seemingly no reason? There could obviously be many reasons for this condition: fuel delivery, ignition, timing, etc. That means there are lots of tests you must perform to see what exactly is causing this problem. If you have a fuel problem, then you'll likely smell it. Timing issues can usually be solved by checking the TDC marks on the crank and camshaft pulleys. Ignition problems, however, require voltage and resistance tests to pin down. You have to test your spark plug wires your ignition coil(s). Since tens of thousands of volts are required to make a spark, the resistances that you are going to measure in the cables and the ignition coil are also in the thousands of ohms. Always check your vehicle's factory service manual for proper specifications, but if you find your ignition coil is to blame for your misfires then you'll have to replace it ASAP.
What do ignition coils do in your engine?

Mechanically timed ignition has been around almost as long as automobiles have been, though advancements in technology have certainly changed how components of the system work together to provide an accurately timed spark. Central to all mechanically timed ignition systems is the distributor; however it wouldn't be able to do its job without receiving thousands of volts from the
ignition coil. Your spark plugs require somewhere around 50,000 volts delivered at precisely timed intervals. Since your battery is only a 12-volt power source, the ignition coil has to step up the voltage and release it to the distributor as needed. This process happens several million times for each year the vehicle is in operation. So whether you have a central ignition coil powering a distributor or you have an ignition coil on each spark plug, it will eventually fail.
D.I.Y. steps for both styles.
Replacing an ignition coil is usually pretty easy. It involves your car's electrical system, so certain safety precautions must be followed. Always unplug your battery first. The rest of the steps will be different depending on the type of ignition system you have.
Mechanically timed ignition - Single ignition coil
- In this type of system, your ignition coil has two poles on top of the cap (connecting to the ignition switch on one side and the contact breaker and capacitor on the other) and one central terminal that leads to the distributor.
- Disconnect and unplug all wires, and remove the coil from its housing.
- Clean off all the contacts, and reconnect the new ignition coil. At this time, you may want to install new spark plugs.
- Finally, reconnect the battery and you're done.
Electronically timed ignition - Coil on each plug
- In this type of system, you will have a coil on each plug or every other plug that are pulsed by a computer (sometimes called an ignition control module) and connected by a wire harness or high tension leads.
- Disconnect the wire harness (or spark plug wires if you have them), and unscrew the coil from the cylinder head.
- You can take this opportunity to change the spark plugs and/or wires if you desire.
- Reconnect the new ignition coil, then the battery. You are done.
Only trust the best parts when fixing your engine.
Buying new ignition coils can sometimes be a confusing task. There are many brands out there, and not all are good quality. At Car Parts Discount, we offer the best brands from high quality reproduction manufacturers and the original equipment. For the budget conscious, we have less expensive replacements as well. So if you find yourself stranded and need a new ignition coil, take advantage of our low prices and fast shipping. Order online today and save.