My Truck Won’t Start – Troubleshooting a Failed Ignition

The worst experience at any time of the day could be when your truck won’t start. Several reasons lead to this, including a failing ignition, and a faulty fuel pump. You will need to troubleshoot your ignition in such a scenario. Doing it is a harmless job, and you will not be hurt if you apply common sense.

When troubleshooting the ignition system when a truck won’t start, you will be working with a running engine and a high-voltage system. Such can expose you to a nasty shock. Therefore, safety should be your number one priority. Consider the following before troubleshooting a faulty ignition.

  • Always put on safety glasses. Eyes are some of the soft parts of your body worth protecting when working.
  • Avoid hot areas within your engine. Such causes physical injuries. Therefore, put on protective gloves. Gloves will protect your skin. The exhaust area of the engine is usually very hot. Avoid touching it.
  • If possible, disconnect the battery. Doing this prevents electrical shock. Electrical sparks usually look for a direct path to the ground. Your body can be the best.

Necessary Tools – You will require a socket Set, spark plug socket, multimeter, spark plug tester, and a multimeter.

Diagnosing Ignition Issues

Here is what to do to troubleshoot the ignition issues where the truck won’t start.

Verify the Existence of Spark

You will need to verify if the spark plug is firing. Test this using a spark plug test light, or connect the plug to the ground and turn your key. 

Probe for Power

While your ignition is on, break out the multimeter to ensure the ignition system is receiving adequate voltage. If it doesn’t, the next area to check is your battery. If your truck has a ballast resistor ensure it supplies sufficient voltage to the system.

The resistors play the role of lowering the voltage getting into the ignition system.

Double Check the Firing

If your truck is misfiring, you must verify it and check it against the setup on the distributor cap. If you have just finished installing the plug wires or the distributor, you may need to redo the procedure. Such happens to everybody, so never worry.

Double Check the Timing

If you are working with a distributor, you must verify your initial timing. It is challenging to break out the breaker and line up your timing marks while minding your racing. You might find out that the distributor came off the alignment because of a loose bolt that holds the clamp. 

Inspect Spark Plugs

In case of a misfire, focus on the spark plug. Check for any signs of damage or fouling of the plugs. If nothing substantial is visible, use a multimeter to test your spark plugs.

Test Spark Plug Wires

If the spark plugs are okay, consider checking your spark plug wires. If you note any sign of damage, consider replacing the wires. 


Shared in this guide is how to go about a situation where your truck won’t start. Many reasons lead can make your truck fail to start, and a faulty ignition system is one of them. If your ignition is the issue, consider troubleshooting it. The ignition system has various parts that can fail. Upon knowing the faulty part, work on it as soon as possible.  

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