An air bubble in the system is a good possibility.
Jack up the right front corner of the car high as you can. remove the cap from the turbo cooling tank. start the car and cycle the heater. watch for air bubbles to come out. Top it off as needed.
I use either Peak or Prestone coolant.
178,000+ miles, 5/20/12 new ej257 short block, 8/20/11 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. CHECK your oil, these cars use it.
Engine Build - Click Here