Advice on knocking noise.

[Ballintra]

Loving finally being a 997 gen 2 owner but looking for some advice.
When driving on any rough road surface ( and the roads in Glasgow ain’t good ) I am experiencing a "knocking" sound, I have had inner and outer tie and track rod ends and coffin arms replaced but it’s made no difference. What do you think could be the problem or is the knocking "normal"

Thanks for any advice .

Jim

 

[Ballintra]

 

[msamos20]

Owned 2 997 turbos. Had vague knocking sound. Had. Mot done was failed fractured rear offside spring was surprised ! Hsd both rears replaced. Argued that should be covered used Porsche warranty they paid up eventually. Sorted vague knock !
Hope you get sorted Martin
997 great cars

 

[Motorhead]

Jim,

Although sound is directional, in an enclosed cabin very often it’s difficult to establish if the knock is coming from the front or the rear of the car.

The front strut top mounts can also be a source of knocking sounds if you’ve not had them replaced. There are a lot of elastomeric bushes in the multi-link rear suspension which will have deteriorated with age, any one of which could be the source of your knock, so unfortunately it’s just a process of elimination, and a lot force is required to check for play in joints in a static set-up. []

Jeff

 

[STiG911]

Seconded for possible top mounts. Very common on all 997 models.

 

[Reuben_997]

I would suggest the front fork arms. Mine were shot on my .2
Replaced my coffin arms, fork arms and inner tie/outer track rod ends.

Top mounts are prone to making noises as well...mine speak every so often...but do not knock.

I temporarily used a set of H&R springs, as I am still waiting on my Bilstein's to come in & re-used my top mounts. In an ideal world, I would have changed them out for the new ones too - but decided to wait until the new suspension arrives.

It's made a world of difference, with no knocking noises at all and a tighter feel.