Removed backbox, Weird noise!

Action Jackson · Post by **Action Jackson** » Tue May 29, 2018 1:51 pm

Hey all,

I got the backbox removed on my zed today (YAY!) however... (oh no!) i seem to have a weird kinda gasping/rasping/sucky noise coming from the exhaust after letting off the accelerator off, seems to only do it when in neutral or pulling away (haven't noticed this sound on any other videos to do with back boxes)

Took a quick vid and hopefully someone can explain whether i need to be worried or not!

https://streamable.com/yn3cy#

Thanks guys!

Machine monkey · Post by **Machine monkey** » Tue May 29, 2018 3:35 pm

Probably a leak on a weld or a clamp would be my thinking.

Action Jackson · Post by **Action Jackson** » Tue May 29, 2018 4:51 pm

Can't imagine it being anything to do with the weld, they literally cut just before the back box before adding the pipes.

My only thought is it could be something to do with something with the exhaust gas recirculation?

Maniac · Post by **Maniac** » Tue May 29, 2018 4:58 pm

If you’re referring to the fffft noise as the revs come down that’s entirely normal and usually muted a little by the back box.

Ewazix · Post by **Ewazix** » Tue May 29, 2018 5:28 pm

Probably just unsilenced pressure waves,

Takes me back, as it actually sounds like my first car (Hillman Minx with an exhaust repaired with bean tins and 'Gun Gum'

)

mr.tourette · Post by **mr.tourette** » Tue May 29, 2018 7:36 pm

thats normal on a chopped box

Action Jackson · Post by **Action Jackson** » Tue May 29, 2018 8:10 pm

Panic over!

Thanks guys! after watching a few more vids of back box removals on the youtube, i notice quite alot of them have the same noise, just seemed very loud! (the paranoia started to kick in!)

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