Common Ignition Problems

Things not running quite right with your vehicle? Feel like you’re driving on a rough road or using more gas than normal? You might have an ignition problem.

Usually you can identify one of two major issues. If your check engine light is on or flashing, finding the problem is easier. AutoZone’s free FIX FINDER service can help you identify the most likely part causing the issue and make a recommendation for repair.

You might end up needing these

Common Ignition Problems

A side by side comparison of old vs. new spark plugs.
1

Faulty Ignition Coil, Spark Plug or Spark Plug Wires

An ignition issue can be caused by a faulty or failing ignition coil, spark plug, or spark plug wire set. These critical components of your ignition system keep your engine running smoothly. If they have a problem, you'll notice a rough ride, engine misfires, and possibly decreased gas mileage.

Often times, replacing the failed or failing part will correct this issue.

Ignition coils and wire sets can be replaced with a fairly straightforward job. However, some applications will require removal of major components such as the upper intake plenum manifold. Reference a repair guide for more specific information for your vehicle.

Spark Plugs may require more attention. Some spark plugs need to be gapped and have anti-seize applied before installing and some do not. Check the spark plug manufacturer's requirements. Spark plugs should always be installed with a spark plug socket and tightened to the proper torque. If you need a torque wrench, borrow it from AutoZone through the Loan-A-Tool program.

2

Oil or coolant contamination

Another common issue is contamination of oil or coolant on the spark plug boot. If the boot is contaminated, the spark plug tube seal, valve cover gasket or components of the cooling system are failing and need to be replaced.

This issue must be addressed immediately as it can lead to failure of the ignition coil, spark plugs or plug wires.

Pinpointing an issue

To help pinpoint an ignition issue or decode a check engine light, stop by your local AutoZone to use our free Fix Finder service to help identify the most likely problem and make recommendations for a repair.

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