So, she starts fine when the engine is cold, and she'll start fine after being off for a short time (maybe 10 minutes) but if it's nearer 20-30 minutes she won't catch, then when she does it's either a high revving affair or a very weak start that gradually gets going.
Oh, and it's always in a busy car park, when I'm in a hurry

I though I remembered this being mentioned previously but I can't find it now.
Anyone?