Knocking noise

[Tommo.]

Hi guys,

Got a bit of an issue with my Trophy (again!!)- is it me or do these cars just have one niggly fault after another? As soon as I fix one thing, something else needs doing. Fortunately, never anything major...

Anyway, onto this weeks problem- I have noticed a knocking noise when the car is at low speed and sometimes it continues when the car is stationary (even after i have turned the engine off). It seems to be coming from the front drivers side.

I have looked under the car and nothing seems untoward if i'm honest. The only thing I can think of is an issue with the brakes as the knocking predominantly occurs when braking. I fitted new Brembo HC discs and Brembo OEM pads a couple of months ago, the discs still look in good condition and there is plenty of life in the pads. They do have a tendency to squeal a bit, which is not something i've experienced with this type of pad before...

I have also noticed when lifting off at speed, the car seems to slow down (without any braking on my part) a lot quicker than i would expect it to. Furthermore, I have just pushed the car whilst on my drive and i could hear a faint grinding noise from the brakes, as if they were engaged slightly.

Any thoughts? Does it sound like the caliper could be at fault here?

 

[welshname]

For the knocking I'd be suggesting carbon canister.

It's down behind the drivers arch liner behind the bumper.

 

[Tommo.]

For the knocking I'd be suggesting carbon canister.

It's down behind the drivers arch liner behind the bumper.

Doesn't the carbon canister make more of a ticking noise if it fails?

Should also add that i did have the brakes bled and fluid replaced and the knocking started shortly after, but it could just be a coincidence.

 

[welshname]

It's the only thing that would still make that noise with the engine off. Put your hand on it when you can hear the knocking. You'll feel it in the canister.

 

[Tommo.]

It's the only thing that would still make that noise with the engine off. Put your hand on it when you can hear the knocking. You'll feel it in the canister.

Ok thanks mate. I can probably borrow another carbon canister to try so i'll give it a go.

Strangely it's only made the knocking noise once today (over 50 miles or so), i tried to get out of the car in time, but didn't catch it lol!

Anything else it could be?

 

[welshname]

You ever get anywhere with this?

 

[Tommo.]

You ever get anywhere with this?

Hi mate.. apologies, i've only just saw you'd posted in here!!

Sadly i've had no luck in finding the cause of this. I checked the carbon canister as you suggested, but it all appears to be in good working order.

I've got some anti-rattle shims to put in the front calipers. I'm now running OEM pads up front without any shims, which i understand can lead to the pads moving around slightly, causing a bit of a knock/clunk at low speeds. I'll stick them in tomorrow! It's a long shot but i'm not sure what else to try.

It still doesn't explain the clunking/knocking when the car is stationary though? I have searched online for hours but it seems nobody has experienced this before

The problem is intermittent and as is always the case with this kind of thing, it never happens when i try and show somebody else....

Anyway, thanks for taking the time to reply, it's always appreciated

 

[welshname]

Only other thing I can suggest for the stationary noise is just the exhaust cooling down. The ping and click as the metal cools again.

 

[Tommo.]

I know the noise you mean with re. the exhaust, but i'm not sure it's that. It's quite a noticeable clucking noise and you can feel it through the footwell when the car is stationary. I'm still convinced it's brake related but i have nothing to back it up other than the fact it seems to be coming from that area.

It started shortly after the brakes were bled... could it be air in the system or something like that?

 

[ldubl]

Did you find the problem / solution to this Tommo?

I have exactly the same symptom on a Trophy, you described it perfectly!

 

[Tommo.]

Did you find the problem / solution to this Tommo?

I have exactly the same symptom on a Trophy, you described it perfectly!

I did indeed. One of the front spring had moved out of place, I re-seated it and it has been perfect ever since.

 

[ldubl]

I did indeed. One of the front spring had moved out of place, I re-seated it and it has been perfect ever since.

Excellent!

Fred's top mount washers sorted mine