hard to start when engine is warm can anyone help

I get this too (I've got 90bhp 1.9Tdi). I usually just keep cranking and hold the throttle down slightly - gets in going in the end.

Would be interested to know why though!

Temperature sensor in the injector pump (can be repaired by a derv injection specialist and you don't need a whole new fuel pump).

Also check the vacuum pipes.

I take it you have checked that the glow plugs are working ok, not that it should affect a hot engine.

IIRC sometimes the coolant temperature sensor can have a bit of a funny too.

Sure somebody who knows more on this one will be along soon.

Guys, please answer separately. Does the engine spin as quickly on the starter motor when it's hot as when it's cold?

My car suffers this after a longish drive (as I do daily for work). If i stop for fuel when I have reached my home town.

When I turn the key, it spins at the normal speed (as when cold), but refuses to catch for about 5 seconds, and then starts. Mine has a new coolant sensor a few months back, and then a while later I noticed the problem starting, but that did then coincides with me changing jobs and then having a long commute to/from work.

Try searching for egr (exhaust gas recovery) valve on this forum. I changed my starter motor after similar symptoms only to find egr clogged with gunk.