Spark plug resistance testing

I was perusing the archives and saw a mention of how someone tested the resistance of new plugs before installing them. Apparently he had on occasion found a few “bad” ones. Anyone know what figures I should be looking for and how to set the multi-meter to take this reading?

Gerard
BPR5ES

Oddly enough their was a mention of B K R 6 ES in the parts book which might be the same plug but with a different size hex head???

I can only think of a high resistance spark test, a device that hold the plug, view spark, check the gap,
and fire a pre-determined voltage (on the expensive one, otherwise your own coil)

the actual resistance of overcoming the air gap to earth would be many megOhms

Typically 5K. You can test them with a conventional multimeter on the Ohm setting. The problem is that you are measuring them cold, and without any current flowing through them.

Putting the car on an ignition scope will show a duff plug very quickly, but a scope costs a lot more than a multimeter.

Sometimes the resistor (or regular) plugs fail after use, sometimes they are duff when brand new.

Hantech auto scopes can be had for as little as US $200, thinking of getting one for working on later-model vehicles with many sensors hard to diagnose any other way, but great for any Ignition system diagnosis

I only know the ancient Bosch one.

Being able to see what the LV and HV are doing makes some things a LOT easier!

check ebay, they even come equippped with software pre-programmed to make check various generic sensor faults easier for a non-scope non-auto technician person. Chinglish instructions tho apparently

my old scan gauge cost $100, paid for itself first use, used may times since read and reset engine codes

My mechanic notes with my aggressive style of driving; read lead foot! I should be using a BPR 6 ES which is what the auto parts store referenced. There is also a BKR 6ES which has a smaller hex size and is the exact same plug.
All thoughts welcome.

Gerard