Recent rebuild of series 8 fd3s- new rotor housings, rotors, seals and 2nd hand turbos. Port and polish. Not sure why it blew in the first place as it was a recently purchased car. Since rebuild, found oil leak from 2nd turbo oil feed- yet to fix. Now, starts and runs well for 10 mins or more, but upon restart will have lumpy idle and loss of power. Is it likely related to the oil leak from the second turbo or perhaps something else?