NC 3.5 PRHT intermittent rattle when roof down

Technical Area Body, Interior & Styling
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  1. My model of MX-5 is: _3.5 _
  2. I’m based near: Glasgow _
  3. I’m looking for technical help or recommendations on: fixing a rattle

First time post and apologies for being a technical muppet! I have a 2013 NC 3.5 and have the most annoying rattle when the roof is down? The worst bit is it only happens occasionally. The rattle is behind the passenger seat at shoulder height. Has anybody got any ideas on what I can do to try find the source. Thanks so much

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Hiya, has the car got an aftermarket rear box fitted? Resonance can cause the rear parcel shelf to ‘buzz’ at certain revs, had this on my last NC, put in some foam pipe lagging under the shelf which cured it.:+1:
Barrie

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I’ve known the roof panel to rattle when folded on a couple of occasions when driving over very bumpy surfaces (a field for example). IIRC there is an adjustable “stop” on each side and one side required adjusting very slightly. If you are able to reproduce the rattle reliably, ask someone to come out with you and put some hand pressure on the roof panel and see if it stops. They may have to kneel on the passenger seat, facing backwards so you will have to find some private land to do this on.

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If it’s a prht it could be a detached 10mm head bolt from the PRHT control unit behind the plastic panel. If soft top there is a door pocket in the same place. (loose items?) If it has the smarttop foof module fitted it’s in that same compartment and may be unsecured

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Hi Barrie, the car was one owner 11,000 miles and totally original. So cant be a rattle form there. Sounds more like something plastic and loose rattling against something else. The weirdest thing is it only happens when the roof is down and it only happens sometimes very strange and annoying. Thanks so much for getting back to me.

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Thanks for getting back to me. Yes it is a PRHT i will have a look at the control unit as you described. (once i work out where it is !!!) Cheers

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Passenger seat fully forward on runners and you will see the square panel behind it. Mine had a loose screw which holds the cable outer on the unit behind the panel.

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Hi Robbie, great idea i will get my wife to drive and i will sit in the passenger seat and try identify the noise when it happens next time. Cheers

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Hiya, sorry I couldn’t be of any help! Robbie has the right idea, you should be able to touch various areas and see if the noise goes? Hope you get it sorted, these noise/vibration/
squeaks can be annoying to say the least!
Barrie

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Mine does that too. Sounds like someone shaking a cutlery drawer. I assume it is part of the powered roof mechanism not lying soundly when folded.