Robhuughes

Hi so basically I bought this car at the beginning of the year and it has always seemed to have this horrible rattling noise that is only audile after revving the engine and coming off the throttle, please can somebody help me diagnose the issue as its driving me round the bend, cheers.

Robhuughes

Video (sounds like metal on metal):

4.2s5w6spd

Sounds like somethings loose in the intake, take out the airbox and work your way through the intake system checking for loose bolts and damage to the pipes. If you don't find anything then I'd recommend having someone else look at it

Robhuughes

Hi thanks for the reply, Ive had the entire airbox out, dismantled cleaned with a new filter and reinstalled so that eliminates the intake side. However It does sound like it is coming from the CAT or the injectors, I have read online the CAT internals can come loose or the flex pipe can deteriorate and cause a rattle so that is the next step I think. I have receipts from the previous owner for having the timing chains replaced and I am worried it could be related (maybe the chain tensioner?) but having driven it in this state for the past 8 months I think something would have happened by now

I should have added this sooner but the car is a 2011 A5 S-line 2.0 TFSI

Any advice/opinions would be greatly appreciated