2006 Ford Explorer 4x4 with 222,000 4.0 V6 dies at stop lights and Idle.

The problem is a spike in idle or rev in RPM then a low RPM usually low
enough to stall. Sometimes it is fine, but others it sounds like a misfire?
Runs great above 2,000 RPM and highway. Engine codes are not always
present, but when it does show, P0193 Fuel rail pressure circuit high bank 1,
and P2135 Throttle/pedal position sensor/switch A/B voltage correlation.

My question is it wiring or parts related? My guesses are Air, Fuel, or Spark:  
Fuel Pump, or Sensor related, Coil pack? All new plugs and wires 20k miles
ago. Regular maintenance and oil changes. New Air Filter. New fan Clutch.  

I replaced both fuel pressure sensor and the throttle body position sensor,
but still same issue.

Thanks for any help you can offer.