Pull out the plugs you could have smashed the gap on one of the plugs. If this happens it will not fire. This will cause the problem. Allso if the cap was put on correctly when pull off sparkplug wire could have broken contact and pulg will not get spark.
89 yj 4.2, holley 390, clifford manifold, borla ss header, 2.5" bds lift, 1" shackle lift, 31x10.5x15 on stock jeep 8" alum. rims,
86 cj amc 304 bore 30 over, procomp cam, roller lifters, edelbrock intake and edelbrock shorty headers, holley carb, hmi distrib, Be cool raid, 2.5 procomp lift, 33x12.5x15 deep 10" Alum mag, dana 30f, 44r, tf999 auto with lokar shifter, 300 transfer, 8000lb winch, procomp bumpers, body rusted and abused.