Van starts easily when engine cold, BUT....

Hello, sounds like a "hot soak" fuel condition where fuel is volatile with a hot engine. Either way, sounds like a fuel and air mixture issue. Could, of course, be nearly anything related to engine performance - ignition, fuel, emissions, air intake -- so -- seek local guidance at a VW specialist near you. Use this link to find some shops near you that can help with your concern: www.repairpal.com/repair-shops