If you gapped the plugs impossibly wide, it's possible the ignition won't have enough power to produce a spark.

But that's pretty unlikely, as the electrode would probably break before you could gap it that wide.

Answered by Ernest Clark (expert)
1,762 answers provided

If the gap is too small, ignition sparks would be too weak to ignite resulting in non starting.

Answered by KHLow2008 (expert)
39,905 answers provided