How to test spark plug wires with multimeter ?

Before knowing the procedure of how to test spark plug wires with multimeter you must know about spark plug. A spark plug is responsible for starting combustion in your engine. It not only helps in starting but manages it to remain in this running condition. The spark plugs then through this high current to fuel injectors via wires. These wires are the only connection between spark plugs and the engine.

Consequences of not checking spark plug wires

If you’re in the city and your car engine fails, there are much higher chances of getting an automotive technician. But if you’re in a remote area, it will be much difficult for you to trace the fault or find a replacement on your own. The situation can be worse if the weather conditions aren’t in your favor.

And believe me, there are much higher chances that it will happen on rainy days or if you’re stuck in a snowfall. If you’re reading this blog before falling into such a messy situation, then consider yourself a bit lucky because here I will tell you how to test spark plug wires with multimeter and without it. Just be with me,

faulty spark plugs testing

One of the following reasons you might be facing now,

  • The engine will start missing
  • Fuel average will be disturbed
  • The acceleration can decrease.
  • Faces problem while starting your car
  • Engine warning light starts blinking
  • Your car wiring might get burned

How to test spark plug wires with multimeter

This guide is for both beginners and electricians. First of all, you must know which tools should be in your toolkit for troubleshooting. Following are the items.

Tools required to check spark plug wires

  • 1x Auto-Ranging digital multimeter / digital clamp meter.
  • 1x Plier
  • 1x insulation tape
  • 1x Contact cleaner (if it’s not possible that you can use distilled water)
  • 1x large cleaning cloth

Steps 

  1. Expose the area with light so you can see everything.
  2. Start physical inspection of spark plug wires and female spark plug holders.
  3. If you see any damage to insulation, then first insulate the wire with insulation tape.
  4. Switch your multimeter to Continuity.
  5. Touch one test lead at one end and second test lead at the other end. If there is a beep, then your spark plug wire is healthy.
  6. If the beep goes and back or starts missing, there might be some carbon on the clips.
  7. Use the contact cleaner on clips and wash it until all the carbon goes off.
  8. If you don’t have the contact cleaner rinse your cable ends with distilled water and dry them with pressurized air.
  9. Check it will start working.
  10. If you still feel any issue, then you can buy the ACDelco professional spark plug wire set for just a few bucks. 
how to test spark plug wires with multimeter

Best multimeter to test spark plug wires with multimeter

If you want to test your spark plug with a multimeter, you need the best multimeter to test spark plug wires. It can be analog or digital, depending upon your preferences. But in my opinion, a digital multimeter is far better than for automotive use. Therefore, I have also made a list of the 8 best multimeters for automotive use.

Safety Guide

Safety is the priority. But most people take it for granted. If you are new and don’t know about precautions then you might damage your equipment and yourself also.

Always make sure that your car system is offline.

First of all, disconnect your car battery terminals and then start checking.

Must check the fuse box first. If there is any flashpoint there, then replace the fuse first.

Always make sure to use safety Goggles and wear Insulated hand gloves before using a multimeter.

You must have to set the right ranges and then start your measurement. If the multimeter is auto-ranging, then there is nothing to worry about.

Check your multimeter is well calibrated and works properly.

How to test spark plug wires without multimeter

Checking spark plug wires without a multimeter is not a good option. But if you don't have a multimeter, I will tell you some of the best life-saving hacks.

It would be best if you had a screwdriver in your toolkit. Start your car engine and then touch the tester to live wire. But before touching the screwdriver, you must check the screwdriver is insulated well. After touching the wire, if the tester lightens up. That means the wire is functioning well.

Final Verdict

In automotive electrical testing, a little fault can cause major accidents. So, always try to maintain your automotive regularly. While talking about automotive electrical wiring, spark plugs and their connected wires plays an important role. Here I have discussed how to test spark plug wires with multimeter and without a multimeter. In my opinion, the Klein MM700 multimeter is the best electrical tester for automotive use. You can grab the best one which suits you.

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