1999 diesel Polo hot start problem

[dwdw]

I have a 1999 diesel polo. Starts ok on cold, but very slow to fire up when hot (eg 10-30 secs of cranking) and occasionally wont start at all. any ideas??
david

[martin1810]

I would get a fault code read. It could be fuel temp sensor or coolant temp sensor or even air temp sensor. A code read might tell you which area is most likely. As it starts fine and runs ok when cold it suggests coolant or fuel temp sensor.