Something else I learned about starting

[procharger]

I forgot to mention that when I was trying to find out what was wrong, I had

all the plugs grounded to  engine and did a lot of cranking on the engine

until it got fairly slow and the battery got way down, but it still was firing

which was surprising, it was turning way slower than I would have ever thought

and still fired plugs at least the ones that were working.

[Tom Baker]

Just because they will fire in the open air doesn't mean that they will fire in the cylinder under pressure. I have seen many times a sparkplug fire in the tester until the air pressure is turned on, and then they don't fire.

[Anticept]

I've also seen the opposite. It's weird.

[procharger]

My point was engine was turning very slow yet it was still firing.

[Tom Baker]

My point was engine was turning very slow yet it was still firing.

My point was if they were installed in the cylinder they might not have been firing, because of the compression.