6. Engine light Code On / DTC on
Commonly the code is: P0351 (Ignition Coil – Primary/Secondary Circuit Malfunction). If the ignition coil has a malfunction, the engine light code in the combination meter will turn on, and you should use a scanner or diagnostic tool to check the malfunction.
7. Engine hard starting
This symptom will occur especially if your car uses a single coil. If the coil has a malfunction, it means the engine will be cranking without sparks inside all cylinders.
The Average Ignition Coil Replacement Cost
The cost of a new ignition coil depends on the make and model of the car. Some coils are as cheap as $75 while others cost in the $300 range. If you have the replacement professionally done then the labor costs will be between $50 and $100 per hour. Therefore, you can expect to pay at least $150 to $200 if you were to take your car into a professional automotive repair shop and have them replace your ignition coil for you.
Read also: Average Fuel Filter Replacement Costs
How to Test Ignition Coil
To run a test on an ignition coil, first turn off your car’s engine and open up the hood. Locate one spark plug and remove the spark plug wire from it. These wires typically start from the distributor cap and run to the spark plug. Use rubber gloves and insulated tools when working with these electrical components. Take a spark plug socket and remove the spark plug. Now reattach the spark plug to the spark plug wire. Use insulated pliers to hold the spark plug onto some metal part of the engine so that the threaded portion of the spark plug is touching the metal. Remove the fuel pump and get ready to crank that engine. You may need an extra person to turn the key in the ignition because you are holding the spark plug down with the pliers. Once the engine is cranked, look for blue sparks forming along the spark plug gap. If you see blue sparks then your ignition coil is working properly. If you don’t see the sparks or if you see orange sparks then this is a sign of the ignition coil malfunctioning. When you’re done with the test, disconnect the spark plug, place it back in its hole and then reconnect the spark plug wires to it.
Tips: Simple Steps to Test Which Coil has a Malfunction
- Start the engine.
- Keeps the engine running at idle speed.
- Open the no. 1 ignition coil bolt, and then pull up the coil to see the engine’s condition.
If the engine’s condition becomes changed to rough idling, that means the no.1 ignition coil is good. Then you can continue this step with the next ignition coil until you find the engine condition has no change. When you pull out a faulty ignition coil, the engine condition should not change.