987 rattle / grinding at low revs

[Warwickshire987]

Hi all

Recently became the owner of an 89k miles aqua blue 987.2 2.9l, my first Porsche. Car drives brilliantly but just one thing bugs me.

At low revs in 1st and 2nd, mostly when just coming off the bite and pulling away, there's a harsh rattle / grinding noise that sounds like it's behind my right ear.

Found a corroded heat shield washer and replaced this to secure but the rattle is still there.

Local specialist has listened and was pretty sure it was exhaust related. He's had it up and banged around to find anything loose but cannot find the culprit.

Any ideas / similar experiences?

Thanks in advance

Edited October 20, 2022 by Warwickshire987

[½cwt]

You have covered the two normal things, lose heat shield and lose cat core.  The only other I can think of quickly is brake disc stone guard.

[Warwickshire987]

1 hour ago, ½cwt said:

You have covered the two normal things, lose heat shield and lose cat core.  The only other I can think of quickly is brake disc stone guard.

Thanks for response although not sure it could be brake disc as it seems to be connected to the rev level.

Exhaust gaskets looked to be on their way out when we had it up, will get them replaced and hope it's something to do with that.

Cheers

[Warwickshire987]

Following on from the above, just had the exhaust manifold gaskets replaced. No sign of the noise on the 30 minute drive home so would appear to be fixed!

[Warwickshire987]

Following on from the above, just had the exhaust manifold gaskets replaced. No sign of the noise on the 30 minute drive home so would appear to be fixed!

[fewtrees]

Interesting - mine does the same.. Does it go or reduce a fair amount when the car's up to temp?

[Warwickshire987]

4 minutes ago, fewtrees said:

Interesting - mine does the same.. Does it go or reduce a fair amount when the car's up to temp?

Yes it was worse cold (I think) although definitely still present when warm. Giving it more revs when at the bite point seemed to reduce it also.

Next time you have it up check the state of the bolts in your gaskets, apparently a very common issue.

[gillbe]

You had the exhaust manifold gaskets replaced - just to confirm, you mean at the actual engine - to - exhaust manifold ; not the smaller triangular gaskets between cat and silencers?

[Warwickshire987]

12 minutes ago, gillbe said:

You had the exhaust manifold gaskets replaced - just to confirm, you mean at the actual engine - to - exhaust manifold ; not the smaller triangular gaskets between cat and silencers?

manifold to cat gaskets, see link below

https://www.design911.co.uk/fu/prod6585/Exhaust-Manifold-to-Cat-Gasket-Porsche-Boxster_2/

[iborguk]

2 minutes ago, Warwickshire987 said:

manifold to cat gaskets, see link below

https://www.design911.co.uk/fu/prod6585/Exhaust-Manifold-to-Cat-Gasket-Porsche-Boxster_2/

Which if they were original are held in that join with studs made out of Camembert.

[gillbe]

aha - I had the same cold rattly issue and replaced these gaskets and bolts myself recently 👍

 

 

[½cwt]

1 hour ago, iborguk said:

Which if they were original are held in that join with studs made out of Camembert.

Until you come to get them out to fit replacements, and then they are hard as nails.

[Del_tl1000r]

On 10/20/2022 at 10:23 AM, ½cwt said:

You have covered the two normal things, lose heat shield and lose cat core.  The only other I can think of quickly is brake disc stone guard.

Is a loose cat core a common issue?

 

[½cwt]

32 minutes ago, Del_tl1000r said:

Is a loose cat core a common issue?

 

Quite rare but possible.  Only usually after someone has excessively hammered the studs in the manifold to cat flange to remove the rusty old ones.