National average cost of a Ignition Coil Replacement for popular vehicles:
Avg. cost $109
Dodge Grand Caravan
Avg. cost $234
Avg. cost $161
What is an ignition coil and how does it work?
The ignition coil is responsible for producing a high voltage electrical signal powerful enough to create the “spark” needed for ignition. For your internal combustion engine to operate, air and fuel enter the combustion chambers in the form of a vapor. There, the air/fuel mixture is compressed by the pistons, awaiting a source of ignition.
The ignition coils receive low voltage electricity from the battery and convert it to a high voltage before sending it to the spark plugs. When that high voltage current courses through the spark plugs, it jumps a gap between the center and side electrodes. The result is an electrical arc that ignites the air/fuel mixture, creating enough energy to move the pistons to “pedal” the crankshaft and develop power.
On older vehicles, a single ignition coil might send the high voltage current to a distributor where it is “distributed” to each of the spark plugs at just the right moment. Other engines feature electronic ignitions with multiple coils that respond to the direction of a computer module, thereby eliminating the need for a distributor. Or, in the case of many modern engines, a special electronically-controlled coil sits atop each spark plug.
How do I know if my vehicle needs an ignition coil replaced?
When an ignition coil goes bad, a number of symptoms can occur. Some of those symptoms mimic other problems, therefore it is important to take your vehicle to a trusted technician for a diagnostic scan and accurate diagnosis. Signs of a bad ignition coil include
Your engine shakes or runs poorly
Reduced power output from the engine
A reduction in fuel economy
Your vehicle fails an emission test
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There are 50 shops within 20 miles of your location.
Ignition coil replacement procedures differ from one vehicle to the next. The major differences between these procedures relate to the type of coil(s) used on an engine. For instance, older vehicles that feature a distributor operate with a single coil that is often mounted somewhere in the engine compartment. Distributorless electronic ignitions might have a bank of coils mounted on top of the engine. And Coil-On-Plug (COP) systems have a coil attached to each spark plug atop the cylinders.
To replace a coil, the battery must first be disconnected. An engine with a bank of ignition coils will require that a technician gain access to the coils by removing any guards, shields, or other components that are in the way. Once the bad coil is identified, it is unplugged from the spark plug wire and disconnected from the wiring harness if applicable. The coil is unbolted, removed, and replaced. The technician must be careful to reinstall the spark plug wires to the correct coils.
With COP systems, a wiring harness plug must be detached from the coil. The coil is then unbolted from the engine and pulled from the top of the spark plug in the cylinder head.
OTHER QUESTIONS CUSTOMERS ASK
Can I drive with a damaged ignition coil?
You might be able to drive with a bad ignition coil. Then again, you might not. Sometimes an engine will tend to stall when an ignition coil fails. Other times the engine will not start at all. But in some cases, your engine will simply run poorly with decreased fuel economy. Unfortunately, if you let a bad coil go on for too long, other components can be damaged, such as the catalytic converter, control module, or even the engine itself.
How often do ignition coils need to be replaced?
The lifespan of an ignition coil really depends on driving conditions and the year, make, and model of your vehicle. An ignition coil can last anywhere from 80K to 200K miles.
Can bad spark plugs cause coil failure?
Yes, a severely worn or damaged spark plug can make an ignition coil work harder than it should. For instance, if the gap on the spark plug is too wide, or if the electrodes are fouled or damaged, the coil will try to compensate for increased electrical resistance. This extra effort can cause the coil to fail eventually.
What parts are related to a Ignition Coil Replacement?