Sometimes when I pull away theres a rattling sound coming from underneath the car, personally it sounds abit like a heatshield loose on converter as I had that in last car, only does it when pulling away from still or slightly when going from second gear slightly doesent do it all the time,, ive tried revving stood still but it does not make the noise, don't do it in any other gears, got it booked in for week and a halfs time just looking to see if anyone can shed any light cheers.

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Just had a similar noise on mine, it gradually got worse to the point it was a constant rattle and turned out to be the rear/secondary cat. Sounded like a marble in a coke can.