Take that big plastic cover off the engine, get a good flash light and take a look around.
May be a loose hose at the turbo cooling line...after it was replaced before the last owner sold it...just thinking out loud there....
I left that line loose when I replaced my short block.
195k, 5/20/12 new ej257 short block, 8/20/11 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. CHECK your oil, these cars use it.
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