[Engine] Warm starting problem

[blartbox]

My Berlingo isa 2000my 1.4i petrol. From cold it starts & runs perfectly. When hot, it will also start & run perfectly. Leave it for 30-40 mins after running at normal temp however, & re-starting is difficult, requiring 3 or 4 attempts. It also runs roughly for a few seconds before clearing, then it runs normally. When this happens there is a stong smell of petrol from the tailpipe, suggesting overfuelling. I'm thinking that maybe there is a dribbling injector that leaks fuel when the engine is stopped, or maybe that the ECU thinks the engine is stone cold when it is still partly warm, & therefore enrichers the mixture resulting in partial flooding. (? due to a faulty engine temp sensor). I would be grateful for any ideas, diagnostic test suggestions etc.