Which workshop was this at?

I would see a subaru specialist (STechnic, MMS, Racetorque, ASG etc) for their diagnosis and estimate to repair the car. I'm guessing something hasn't been installed correctly in the first place, causing your issue.

As for asking the seller for some money to fix the car, no chance. Buyer beware.

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[COLOR="Gray"]550Nm off a 2L... Just wish it was in the dak dak...[/COLOR]