SR20det non firing piston

SON240sx Automotive
1

I have a 1990 hatchback s13 sr20det redtop, car is running rough; really shaky engine . Black smoke coming from the exhaust. And also very boggy. So I think the piston is not firing. I take the coil on plugs off and in the hole where the plug goes on cylinder 3 its darker then the other ones and smells like gas, what’s gone is it my spark plug or coil on plug or is it something I don’t want to know about!
Please help get her back on the road!

Thanks
Chaz

2

is the spark plug tight? try unplugging another coil pack and plugging it into #3, if it starts firing you got a bad coil.

3

Thanks for proving I’m a total idiot the spark plug is loose tightened now its fine I don’t know how it backed itself off but who knows thanks again please delete
Chaz

4

lol once apon a time i didnt tighten one down also. it happens