problem wiv my civic, can u help?

its a esi (16v vtec).

if its been driven quite a bit, and it gets warm, it doesnt always start straight away.

i try once, twice, three times, and it doesnt fire up, but then on my 4th time its fine.

its only when its warm, and as soon as its fired up it goes fine!

any suggestions? i.e engine prob, electrical prob??

no immobiliser if fitted