Why is my car knocking when I go over bump?

[Murpheeee]

I have a '93 Mazda 323.
I have had it about 3 years and its now around 96000 miles.

I just spent a tonm of money repairin the gear shifter linkage and renewing brake pads/calipers/rotors.

Just when I thought everything was running well again, today it starts knocking when I go over a bump in the road. It's not a dull knocking, more like something bolted down is coming loose, like a metallic thunk. Seems to only be coming from the passenger side.

Some bumps I will not even hear the sound, and other times I will hear it with every bump or crack in the road.

I have rocked teh car on its shocks, but they all seem to be fine, and visual check shows no broken springs or loose items.


Can anyone help? I really cannot afford to take it back to a shop again right now.

 

[blakeatwork]

I had something similarly on my car. Turns out it was just a loose coupling. Best bet is just to get underneath, and see if you can wiggle anything more then normal...

 

[phantom309]

Two possibilities - whoever did your brakes didn't put the pad retainers back in correctly and one popped out - causing the pads to knock around a bit in their mounts. Or, you might have a worn strut bearing (also caled a strut mount) on the pasenger's side.

Hope it's the brakes: the sound is annoying but fairly harmless and very cheap to fix. New strut mounts usually require the entire strut assembly to be taken apart, and once you've gone that far it's usually wise to replace the strut cartridges as well.

 

[amnesiac]

My first thought is the same as phantom309's - I had to deal with a loose strut on my old truck.
However, a friend of mine had a similar problem and it turned out to be a loose casing on one of the shocks. That could be the problem.

 

[DougK62]

Originally posted by: phantom309
Two possibilities - whoever did your brakes didn't put the pad retainers back in correctly and one popped out - causing the pads to knock around a bit in their mounts. Or, you might have a worn strut bearing (also caled a strut mount) on the pasenger's side.

Hope it's the brakes: the sound is annoying but fairly harmless and very cheap to fix. New strut mounts usually require the entire strut assembly to be taken apart, and once you've gone that far it's usually wise to replace the strut cartridges as well.

WAY more than only two possibilities. A deterioration of nearly any suspension part up front can cause irregular thunks.

I would first check things like tie rod ends, strut mounts, and any other bushings and such down there.

Does the car still seem to drive fine?

 

[iamwiz82]

it could be any bolt on the car. go under there and start tapping until you hit the exact same sound.

 

[Murpheeee]

Does the car still seem to drive fine?

It seems to, I have been kind babying it as I was unsure what the noise was or if something was going to fall off.

 

[Murpheeee]

Originally posted by: phantom309
Two possibilities - whoever did your brakes didn't put the pad retainers back in correctly and one popped out - causing the pads to knock around .

Is this true of loaded calipers?
The ones I got had pads already in them.....do they have retainers too?

 

[MomAndSkoorbaby]

Damn cars...it always seems that when one thing goes wrong, everything does!

 

[Kadarin]

A similar problem on my g/f's Mustang a short while back turned out to be a tie-rod end that was missing a couple of bushings.

 

[Vic]

My first thought was bad tie rod end.