Ignition Coils, Coil Packs and Direct Ignition Coil Units

Karlyn/STI distributes a comprehensive line of high quality Import & Domestic Ignition Coil-on-Plug (COP) components.  Our engineers work closely with our suppliers to monitor and optimize the performance of our Ignition coils.  We also utilize independent engineers for diagnostic testing to maintain the integrity of our coils, plus we utilize German quality windings.

Many of our European coils are manufactured by Bremi Fahrzeug-Elektrik of Germany.  Their expertise as an OE manufacturer of ignition parts can be found in all the aftermarket coils that they produce.

Our COP units feature:

Consistent high voltage output for optimum performance

  • State of the art epoxy injecting procedure which eliminates air pockets and prevents thermal breakdown while also exhibiting high dielectric properties.
  • Expertly wound coils on durable bobbins for long and consistent service life

Note: A fouled spark plug can damage the Coil-on-Plug unit.  We recommend that you always replace the spark plugs when you replace the COP units and that all the ignition coils be replaced at the same time.  As a form of preventive maintenance we suggest this be done every 60,000 miles.

Coil on Plug (COP) Warranty and Diagnosis

Karlyn Industries/STI distributes high quality COP components. We utilize independent engineers to monitor our coils and test warranties. Most coils that are returned DO NOT have a problem.

Rough running engines that set misfire codes can have multiple causes. It is the responsibility of the dealer/installer of our products to verify that the following items of inspection have been performed,  in order to comply with warranty replacement.

General misfire codes are most likely due to an intake vacuum leak or fuel delivery problem. Misfire codes identifying a particular cylinder are usually due to a fouled spark plug, dirty or dead fuel injector or loss of compression in the cylinder (burned or bent valve, weak or broken valve spring or leaky head gasket.)

If the crankshaft position sensor fails, the loss of the basic timing signal will prevent the system from generating a spark and the engine will not start or run. A failed driver circuit within the powertrain control module (PCM) can kill an individual coil and prevent that cylinder from firing. Replacing the coil without addressing the cause will only result in another damaged coil.

Misfire codes can also be triggered from a damaged wire harness due to poor grounds. Inspect the wire harness carefully. You may have to cut back the insulation to verify that there is no corrosion or melting of the wire harness due to poor grounds. A faulty harness can cause the coil to fail. If you simply install a new COP it may seem like you have corrected the problem but, merely replacing the coil without repairing the grounding problem may result in future coil failures.

In summary, it is important to remember that ignition misfire can also be caused by other factors such as worn or fouled spark plugs, loose or damaged coil connectors or terminals, dirty fuel injectors, low fuel pressure, intake vacuum leaks, loss of compression in a cylinder, even a tank full of “bad” gas contaminated with water. These other possibilities should all be ruled out before a COP unit is replaced. (Note: A fouled spark plug can damage the COP. We recommend that you always replace the spark plugs when you replace the COP units & that all the ignition coils be replaced at the same time. As a form of preventive maintenance we suggest this be done every 60,000 miles)