Updated at: 18-01-2022 - By: Lucas

Many motorists wonder whether resistor or non-resistor spark plugs are preferable. Resistor-type spark plugs have an inbuilt resistor that reduces the loudness of the ignition created when you start your vehicle. It’s possible that the noise you hear when you turn on the ignition is caused by RFI or EMI, which are radio frequency interference and electromagnetic interference, respectively.

Disruption of electronic communication signals can be caused by either of these two types of noise. Because of this, the sound system and cell phones will be affected. Engine management systems and two-way radios are also susceptible to interference.

The resistor spark plugs are different from the non-resistor spark plugs in a number of ways. So, here we go.

Is There a Difference Between Spark Plugs That Use Resistors and Non-Spark Plugs?

The distinctions between resistor and non-resistor spark plugs intrigue a small segment of the population. The spark produced by a resistor spark plug is not any hotter. Because it is in its original state, it will have a lower voltage when it is connected to the plug because of this.
Lower voltage sparks can be used if the temperature is colder. A resistor wire is used to reduce radio interference. To jump the gap, a higher voltage is required, which the resistor plugs provide.

In other words, you’ll boost the spark’s overall energy output. Because of this, a resistor plug can elevate the voltage enough to cause an insulation failure in older coils. The distinctions between a resistor and a nonresistor spark plug can now be discussed.

Increased Intensity

In terms of generating the highest arousal, the primary distinction stands out. Because spark plugs are the ones that ignite the engine at startup, they must produce more spark. In general, non-resistor plugs have a more strong spark than resistor plugs.

Spark energy is being resisted by the resistor type. Non-resistor racing plugs are also the primary rationale for their use.

Interference with Electromagnetic Energy

The electromagnetic interference is the source of the second discrepancy. If you’re running a vehicle with a board computer system to monitor and manage engine performance, resistor spark plugs are a must-have accessory. The resistor spark plugs are minimizing electromagnetic interference as a result of this.

It’s also a good idea if your car has any other kind of electrical system on board. Engine computers, two-way radios, GPS, or other systems approved by the manufacturer are included in this category of electronic devices.

Using a non-resistor plug is also claimed to have negative impacts on the engine in some specific situations.

Interference from radio waves

The radio interference is the third difference.. Non-resistor spark plugs are said to offer no benefit in terms of radio interference, according to some. A non-resistor plug, on the other hand, can result in more unwanted radio interference (EMI).

Which Spark Plug Is Better – Resistor Or Non-Resistor?

Everyone’s answer is different. Non-resistor spark plugs may not be beneficial to certain people. The voltage generated by today’s ignition coils is more than adequate.

You’re causing more radio interference by using a non-resistor plug, according to the experts (EMI). That’s because using a non-resistor plug raises the voltage and current over the ground substantially.
Remove the resistor from the plug and you’ll see an even greater gain in power. A non-resistor spark will raise the voltage at the spark plug’s terminals.


When it comes to spark plugs, there has been a long-running argument about whether type is better: resistor or nonresistor. Every person has a unique perspective, so there is no right or wrong answer.

Everyone has an opinion on the subject. You may get a sense of how they differ from each other from the list above.