Knocking sound from under the car.

[steph290504]

Hi,

I have a peugeot 206 S reg 1.4.

I have recently stated hearing a loud kocking sound that is coming from somewhere under the car. I have given the exhaust a wiggle but it seems to be quite firm still and i recently had the back pads fixed so i dont think it would be the bearings as i would have thought they would have been picked up? (the car was knocking when i had them fixed).

I thought maybe the spare tyre holder could have come loose as its empty but it is still quite solid! Does anyone have any ideas what it could be?

I am putting it in for an MOT this week, would this be something that would be picked up during or would it be best to mention it? This car seems to be a money pit at the moment and im pretty clueless about things like this.

[danielr]

does the knocking come at a specific time? or it it all the time?

does the knocking increase with speed or does it get worse when you're idling or sitting in traffic?

does it get worse/more apparant when you're driving and turning the corner?

it it a high piched knocking? or a low pitched knocking?

what sort of frequency is the knocking? (like how many knocks per second -not exactly) does the speed of the knocking increase with the speed of the car, or does it increase with the speed of the enginer revs?

any ideas where abouts the knocking is coming from? is it more towards the back or more towards the front?

is it a knock, or more of a rumble?

does the knocking happen when the car is in neutral, or when it's in gear? (or both), does it go away when your foot is on the clutch?

[steph290504]

The knocking starts as soon as i pull away and continues until i park. Occasionaly it stops when i am on a nice smooth road but generally it is a constant knock.

It doesnt get louder the faster or slower i go it just continues knocking away no matter what i am doing. It only stops when i stop, so when i am idling in traffic i cant hear it banging.

It isnt a high pitched sound, its a proper rattling/knocking sound. At first i thought something was in my boot knocking on the side but after emptying it and still hearing the noise i think it must be coming from underneath near the back.

I took my sons friend out in it the other day and he said it sounds like my wheel is going to fall off

Slightly worrying!

[danielr]

ok,

this is good.

if it's definitly from the back you can probably rule out anything in the front, such as CV joints, exhaust manifold or anything else that'd make annoying noises there.

Are you able to jack the car up and try spinning the wheels by hand. and see if you grip the wheel in both hands (at 3oclock and 9oclock) is there any play in the wheel?

to do this you'll need to leave the handbrake off obviously, you before you jack the car up remember to chock the wheels using a brick, or big stone/piece of wood (or the chock that comes with the jack in the boot if you still have this). -for safety so the car doesn't roll off the jack.

if the wheels revolve freely and there is no "play" then you can pretty much say that the wheel bearings are ok.


then you'll need to move on to checking that.
the suspension is solid (or as solid as it should be)
there are no stones/lumps/bludges/parts where the tread is missing in the tyres.
that the spare wheel is properly attached and that there isn't something sitting inside of it.

There aren't a lot of parts at the back of the car, so not really a lot that could go wrong!

[steph290504]

Thank you for your input.

I will get someone to jack the car up and we can have a nose around.

Hopefully its something stupid thats loose rather than another big expense this close to xmas!

I will post back and let you know what it is, in case anyone else is experiencing something similar.

[philkerman]

I smell anti-roll bar drop links.

[steph290504]

I that really bad, as in dangerous and or expensive?

[philkerman]

Originally Posted by steph290504

I that really bad, as in dangerous and or expensive?

Cheap as chips, easy to fit and knock like an absolute bastard when they've gone.

[steph290504]

That could very well be the problem then, as it is a constant noise. It sounds like i've locked someone in the boot and they are trying to get out

Will stick it in for an mot and ask them to check then. Im going to sound a little bit mechanical savvy now at least.

[steph290504]

Also..

How many drop links are on a car? When i bought it i had the front drop link fixed by a garage about 6 months ago.

Just wondering if they did it correctly or if they fixed the front and now the back have gone?