I have recently bought a Chevy suburban 2000 with a 5,3 L vortec engine.
The engine starts easily when it is cold, but it is very difficult to start when it is warm. Its also smells a lot of gasoline when it starts warm.
Can it be something with the cold start system? Any body knows?
Bjoern

Sounds like vapor lock. Fuel evaporates when it's hot and it won't pump. So you might have a bad fuel pump or fuel filter or fuel regulator. So start with an intank fuel system cleaner and see if that helps.

I would also agree with shnormo about checking the fuel regulator.

It could also be the temperature sensor is faulty thinking the engine is cold....it sounds like it may be too rich if you smell gas.

Do you have a Check Engine light on ??