Originally Posted by
kidsRS
Sounds like a cold start problem to me. your valve might be knackered or the wiring
As said, had exactly this on my S2. Used to dicsconnect the plug and it started fine. When I got bored of that, replaced the valve and it was fine.
Next time it won't start disconnect that blue plug and give it slight throttle as you turn it over. If it fires straight up valve will be the problem.