Rear Suspension Rattle/Heat Shields

[Andy S]

Hi folks, I'm new to this forum, but was wondering if you could help with a couple of things?

I have a 1999 Boxster 986 with 98.000 miles on it which I bought about 3 years ago. I have become increasingly irritated by a rattling/clunky noise at low speeds on uneven roads, which I think is coming from the rear suspension. It sounds as though its coming from just behind my head (I'm not tall...), I dont hear it on motorways, and its not as obvious with the roof down either It almost sounds like a solid plastic rattle, not metallic. Any suggestions?

I'm also slowly being driven mad by rattling heat shields. Every time I've had the car serviced or in for work (I only ever use PC Newcastle or a local independent Porsche specialist), I've asked to have them checked, and every time they come back sorted, but the problem always returns within 2/3 weeks. It's really embarassing when driving round car parks etc. Is it my driving style? Can I have them taken off altogether? or could it be symptomatic of another problem?

Sorry for the essay, but would love to hear your thoughts.... apart from these niggles, I love my Boxster!

thanks in advance folks.

Andy.

 

[911sse]

Two very common issues to be honest.

Stick it into a good independant garage and they'll take care of these items for you unless you feel handy with a spanner, which is far beyond my skills!

The costs are not daft either.

 

[Mark_Bennett]

The heatshields should not come loose for a few years after new fixings are used.

You can do it yourself - the parts are about £5 for each set of fixings and you need 6 sets. Replace all 6 and you shouldn't be bothered for a couple of years or more.

 

[Buddy]

Regarding the plastic "rattle", have you checked the storage box below the roll bar? Is it secure and are the sliding doors in place?

If it isn't secure it may be tapping underneath the underside of the roll bar. Also is the passenger seat belt hitting the back of the seat etc?

On the heat shields, as Mark says the fasteners are available and not expensive but when I had the heat shield noise on my Boxster S it was most apparent when driving around car parks as it echoed around, I changed the fasteners ( 90 deg turn items as I recall ) but the shields were corroded around the holes and I don't remember if there was any washers to engage the pins, the fasteners luckily stayed in place, it is possible that you may have one or two positions which tend to lose their pins.

Unfortunately, I don't have the PET List for the Boxster.

 

[Timbo2]

Re heat shields, recently did mine, what a difference it made, hadn't realised how much they were responsible for noise up through the gears. Its a simple enough job if a little fiddly, my shields had corroded around the holes so I pop riveted a piece of metal over and re drilled it. When I took the fasteners of they were completely shot, not tension in the part that holds the screw. I also noticed that a fastener had failed that secure the heat shield under the boot.

 

[Andy S]

Thanks for your advice guys.

I suspect the heat shields are corroded too by the sound of things and the age of the car.

Andy.

 

[Mark_Bennett]

The fasteners are usually the things to go - unless the heatsheilds are like Timbo2's you shouldn't need to change the heatsheilds. They may not look pretty but no-one can see them so no matter. The fasteners however are invariably not re-usable. Well worth getting a couple of spares.

 

[pacemaker1000]

i had identical problem and it turned out to be the anti roll bar bushes!
cheap and quick fix. 15 mins max for a diy and cost around 20 quid

 

[sawood12]

Your clunky rattle at low speeds could be a failed spring. I know of two Boxster owners who have suffered rear spring failures. The first guy had it on the previous model Boxster and I recommended he take it to the specialist I used to take my 944 to. He fount it straight away - it was the last 270 - 360 degree's off the top of the spring. He commented that it was the first time he'd ever seen that on a Porsche.

However the second guy who is a work colleague with a newer model, took his to the OPC as his car is still under warranty and they seemed to be not particularly surprised and replaced it under warranty - so not sure if this is an emerging issue with Boxsters.

It also seems to be a much more common failure on newer cars these days - I know of a few other people with other cars to whom it has happned also on my dad's Merc. He had a real spat with the Merc dealer who initially were only prepared to replace the springs under warranty and not the damage it caused the inner wings when the front of the car dropped (both springs failed simutaneously). Anyway, they repaired the whole thing under warranty in the end. Apparently, according to one of the mechs my dad spoke to when he picked the car up, it is due to springs being sourced from Easter Europe, the inference being the use of cheaper quality Steel. His opinion of course.

 

[jerry]

Hi, I also have a 'Clonk' from the rear suspension that I am trying to trace. The anti roll bar bush looks worn to me (please see picture) does anyone know if this could be the cause? Thanks

 

[Buddy]

It definitely looks to be a prime candidate, and from what Pacemaker said above may as well do it to discount it from any list.

 

[David JAMES]

For info, I had a similar clunking noise coming from behind the driver, sounded like a couple of planks of wood in the boot and only noisy when travelling at slow speed over my local potholed roads. I mentioned this to the technicians at yesterday's OPC Cabriolet Service Clinic and they told me it is probably the rose joints, high up on the rear suspension, which act a bit like a tuning fork. Apparently this is nothing to worry about, just a bit irritating.

DJ