Car question

[tw]

Originally Posted by glatt

Using a powerful conductive tool to crush a high voltage component. Damage it and get a shock too.

Necessary for testing is to hold a spark plug to the block. Also noted was to not use hands to hold anything. Why would anyone assume vise grips are held by a hand? Pliers obviously hold a spark plug to the block so that a human does not. And so that the better test will work. Obviously something that is not human must hold a spark plug in contact with the block. Why would anyone assume otherwise?

Using vise grips was a best solution that obviously does not cause damage. What was obvious should not need explaining. Something must hold a spark plug's steel body to engine block steel. Why would anyone assume a human holds anything?

Two electrodes per plug was a sales gimmick decades ago. And obviously a sales gimmick today. A spark will cross only one gap whose distance is less than defined by voltage. Irrelevant is it using alternative electrodes. Because a spark only crosses one gap with each spark - meaning it works just like a single electrode spark plug.

Scam manufacturers once hyped spark plugs with multiple contacts. It did nothing useful. More important than multiple contacts is a plug's heat range. Integrity of its ceramic insulator. And how to install it at a proper torque. Did a salesmen forget to mention other and more important parameters to make a sale? When spark plug voltages were so low (ie 18,000 volts), then a spark's gap was important. Today, we no longer need adjust gaps to within 0.01 inches.

Spark plugs once required frequent replacement since metal was of lower quality. Spark plugs are now made using higher temperature metals meaning plug wear and replacement is now rare.