5 replies to this topic

[silver_toes]

Hi All,

 

I'm investigating a knocking noise which i 'believe' is suspension related on the nsf corner of the car

The car is a 97 mpi pretty much factory spec

 

A few weeks ago I was driving merrily through the Yorkshire Dales when I realised i'd taken a wrong turn. I turned around with full right lock on and heard something go thump. (It sounded like something breaking)

Stopped and had a look underneath but couldn't see anything obviously broken. A few metres further down the road I notice a new clunking noise every time I went over a bump/pothole in the road.

The clucking happens whether it's under power or not.

If I just drive down a perfectly level road there is no clunking, It only happens when the car is moving up and down

 

I've got the car home and jacked it up to have a good look around, her'es this things I have checked so far:

I can' see anything obviously broken,

There's no movement in the wheels when trying to move them 12-6 and 9 - 3.

I can't rock the engine front to back

There's no engine movement side to side whilst turning the steering wheel either way.

No play in the ball joints

Tie Bars look fine, no loose bolts or worn rubbers

All the engine steadies look fine

 

Possible issues

One of the rubbers in the top suspension arm his gone, I've not had a chance to check it for play yet

The dampers are very old. I was planning to replace them anyhow so will do that (including bushes). I have taken the old dampers off and they don't feel like there's any defects in them  

I haven't checked the subframe mounts yet

 

Can anyone give some advice on other things that I can check whilst I've got the car in bits ?

 

Many thanks

 

[cal844]

The top arms are metal bushes, have a look to see if the knuckle joint is still where it should be in the cup. The plastic cup wears and breaks up which can give a creak or knock. We had that on my 998 round nose(the one in my Avatar) and it kept knocking until one turn in a junction sheared the knuckle joint
I replaced the knuckle joint and the noise went. Also check for signs that the top arms have been greased.

[luismx123]

I had something similar cus my subframe rubber was gone on the tower bolts. might be worth checking

[silver_toes]

Thanks for the ideas, will check subframe mounts. Would mounts got with a slight clunk/bang if they failed ?

[luismx123]

Thanks for the ideas, will check subframe mounts. Would mounts got with a slight clunk/bang if they failed ?

not sure what it would sound like when it goes, but if they break/split, you get metal to metal contact bouncing on rough roads and with engine vibration. 

[silver_toes]

So, quick update, found the source of the knocking noise as soon as I had the car jacked up.

 

The lower passenger ball joint seemed extremely loose. Removed the hub with a view to fitting new ball joints and discovered that the locking tabs hadn't been bent over on the big washer under the ball joint swivel nut. The ball joint had been slowly undoing it's over the past year or so.

 

Guess I won't be taking the car back to that garage again.

 

Thanks for the help everyone