ive recently bought a W reg 2000 impreza turbo 2000 its my first experience of turbo and 4x4 power. im made up with it but there is a knocking noise comming from the footwell area when i decellerate or travel at 30ish mph in 4th i realise that its not going to be easy to diagnose on here but if anyone else has experienced this problem please let me know what it is or what it could be

 

Any ideas? Driveshaft maybe? Gearbox? Help!!

 

id start looking at driveshaft, then bottom arms, drop links, rack, suspension strut, springs,

well every moving part in that area.

 

I recently had both my front outer cv joints making knocking noises at low speeds, when turning and pulling away from junctions. This knocking/clunking noise gets a bit faster when you increase your speed. Try full lock turns both ways in an empty carpark to see if it's your driveshafts/cv that's making the noise.

To make matters worse I also had a seized O/S front strut making a knocking noise over slightly uneven ground. To start with both of the symptoms were kinda masking each other, but got the car up on a ramp to diagnose fully.
Try driving slowish but in a straight line over some slightly uneven ground and see if the strut is making the noise. If it is, the frequency of this noise won't vary with speed, just the bumpiness of the ground.

I'm no auto-mechanic, but these are just a few things I'd suggest to try and rule out a component or two. Hope it's of some help .

 

Cheers guys at first I thought it was the exhaust but now I'm not so sure...

 

If it only happens in 4th, with no evidence the rest of the time, it's more likely than anything else to be gear damage.

 

No I only said 4th as it tends to be the gear I'm in when cruising at 30 it does it in all gears when decelerating

 

If it's happening whilst not accelerating the chances are it's a seized front strut, which is quite common with the standard units.

What sort of mileage has the car done? Could be the excuse you've been looking for to get a set of coilovers?

 

Lol coilivers are a bit dear aren't they like £800 - £1000+ ? how much is a normal strut? The cars done 108,000 it's lowered on 18's but not sure how much.

 

If it's a drive shaft what's the best way to check? Also if it was a siezed strut I'm guessing that you wouldn't be able to push it down? It's really annoying me as when I test drove it it was quiet and no knocking noises. Typicly it started when I had been driving a good few miles... The guy probably gave it a death ride before I handed over the cash *sigh*

 

Found out today that it was a collapsed wheel bearing which has in turn damaged the hub luckily I've got the bits and a willing mate to do it all for £20! ;-)