Knocking Under Car

[gazatthebop]

Hi,

I have a T plate fiesta 1.25 zetec 5 door. I have started to get a noise underneath, a knocking which coincides with the tyre speed, as if a carpet gripped rod was stuck to one tyre. I have looked around all the tyres and they look fine. When I put the car in neutral whilst driving the noise does not disappear or change sound. The noise doesn't seem to happen in reverse but it could if I reversed at a higher speed.

any ideas?

cheers

[alexandjen]

is it coming from the front?

Maybe a stone wedged behind one of the front brake discs?

[gazatthebop]

front, yes I think so but not 100%. Could a loose brake disc cause the knocking, slight play in the nearside where I think the noise is from, the disc play will disappear once the wheel is on?

[alexandjen]

Maybe take the front wheels off and spin the discs to check how much they are warped

Could also be a failing wheel bearing I suppose but I'd check the discs first

[gazatthebop]

the discs don't look warped. The noise doesn't sound like a wheel bearing, I could be wrong, its like having a stone in your tread but instead of a click its more of a thump but not too low pitched...somewhere inbetween a click and a thump if that makes sense. Is there supposed to be play in the front brake disc when the wheel is removed?

This is not a problem that has been getting worse, I drove to work fine, on the way home it started as soon as I drove off.

[alexandjen]

Most discs have slight play when spun but should be fixed to the hub firmly

Maybe a dry CV joint clicking?

[gazatthebop]

i'll check that out. I've had dry cv's before and it has not made this sound!

[alexandjen]

Did you get to the bottom of this?