I don't know much about reading plugs but the dark burnt looking area on the back/bend of the ground strap doesn't look normal to me.

What does this indicate and should the plug be replaced?

The plugs have ~20K miles on them.









Thanks,
Earnest

 

Just eyeballing it, the gap looks way too open. Otherwise I'd say not too bad, but since they're out, I'd go ahead and replace them, with the proper gap.

 

20k miles? that's just lazy, lol.

 

Gap is .055" on the plug in the pic, I think it was around .059" when I took it out but I had already regapped it before I took the pic.

I think it's just the large pic that makes the gap look huge.

I'm replacing them all anyway, still trying to get the engine shake at 1K RPM to go away and I'm not having any luck.

Thanks,
Earnest

 

Ok boys, help old Earnest out. Engine shake at 1,000 rpm. Hmmmmm... Wha' could it be, wha' could it be...?