15-05-2021, 11:33 PM
In my case all the NGK’s were purchased from a reputable supplier in Auckland. Must be a quality control issue. Testing plugs with a multimeter, digital or moving coil type is only good at revealing plugs with low resistance.
Some plugs may still be leaky but not revealed by a multimeter as the range of Ohms does not go high enough and the voltage the meter uses to provide a resistance measure is quite low, think 9 volt small battery.
Very high resistance, insulator grade like a spark plug, is properly measured with special equipment like the Megga we used in my Airforce days. Not sure what is used these days.
It was hand cranked to generate a high voltage but low current source.
Gary
Some plugs may still be leaky but not revealed by a multimeter as the range of Ohms does not go high enough and the voltage the meter uses to provide a resistance measure is quite low, think 9 volt small battery.
Very high resistance, insulator grade like a spark plug, is properly measured with special equipment like the Megga we used in my Airforce days. Not sure what is used these days.
It was hand cranked to generate a high voltage but low current source.
Gary