Three possibilities for you to consider:
1. Ignition coil breaking down when it gets hot - replace the coil.
2. Coolant temperature sensor faulty - replace it
3. Dirty air filter causing it to run too rich - your air filter should be replaced at regular intervals - when was it last serviced. Easy, and will cost nothing to check the filter.
4. Crankshaft position sensor breaking down when hot - replace it.
Work methodically otherwise you'll find yourself replacing parts willy-nilly at unnecessary cost.