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.  

How To Troubleshoot Faulty Ignition System of a Truck Easily

In this comprehensive guide, we will go through how to troubleshoot faulty ignition system of a truck. The ignition system can be a source of headache in the garage. Especially when your truck runs perfectly, it starts to shake or won’t run in seconds. In such a situation, there must be something seriously wrong with your ignition system, and you must check as soon as possible. This guide focuses on ignition troubleshooting safety and how to troubleshoot the ignition system of your truck.

Ignition System Troubleshooting Safety

Before opening the hood of your truck, ensure you wear safety glasses and gloves, which will protect the soft tissues of your body. When handling the ignition system, you must come into contact with other engine parts and keep off the hot surfaces within your engine.

After opening the hood, locate your battery and disconnect it. Doing this will protect you from electrical shock.

How To Troubleshoot Faulty Ignition System

The ignition system is a chain composed of the battery, the spark plug, the ignition module, the distributor, and the coil. Like the chain, the entire ignition system will not work if any parts fail. Troubleshooting the ignition system will enable you to know the exact part that is not functioning.

Probe for Power

You will do this using the multimeter to check whether the ignition is supplied with adequate voltage. If it is not getting the required voltage, you will have to check if your battery is losing power and correct the issue. 

Sometimes, your ignition might be receiving high voltage. In such a condition, check if your resistor is functioning. In such a scenario, double-check the voltage using a multimeter before checking the resistor. 

Counter-Check Firing Order

If your truck misfires, you should verify the order and check it against your set-up on the distributing cap. Things might be jumbled up as soon as you install the distributor or the plug wires. 

Counter-Check the Initial Timing

Verifying the initial timing is necessary when working with the distributor. It involves breaking out the breaker bar and lining up the timing marks. When performing this procedure, you might be at 180 degrees, or the distributor might come out of the alignment, which can be caused by the loose bolt holding the clamp in place.

Test the Spark Plugs

 Suppose your engine misfires. Focus on the spark plug. Check for physical damages on the spark plug itself. If you can’t notice anything, consider using a multimeter. If the spark plugs are okay, consider using the multimeter to troubleshoot the spark plug wires. 

Test the Distributor

Testing the distributor varies depending on the application you have. To test the distributor, you will check the resistance in the entire system at specific points within the distributor circle. 

Test the Ignition Module

Testing the ignition module is the last step after troubleshooting everything. Testing your module relies on the model your truck has. Do some thorough homework before you test the ignition module.


Hopefully, you now know how to troubleshoot faulty ignition system of your truck, just in case you find yourself having to deal with it. It is necessary to know some of the symptoms of a faulty ignition system, which will help you troubleshoot and identify which part of the system is defective.