Knocking/Tapping speeds up on acceleration....any ideas??

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Jimbob
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Knocking/Tapping speeds up on acceleration....any ideas??

Post by Jimbob »

Not sure this is in the right category as I'm unsure what the darn thing is but here goes...

I was driving the rocco home after work today when I noticed this noise coming from under the bonnet(seems to be right around the area the pedals are).

As mentioned it only occurred when accelerating and was much more noticeable at low speeds and got quicker as I picked up speed. Was driving in London so didn't have chance to get it above 30 mind.

There is no sound when parked up and giving it some...

Anyone got any pearls? I'm stumped though it could be something simple, here's hoping anyway..

Thanks in advance

Jim


bensspares
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Re: Knocking/Tapping speeds up on acceleration....any ideas??

Post by bensspares »

knackerd speedo drive ??????????


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Nate
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Re: Knocking/Tapping speeds up on acceleration....any ideas??

Post by Nate »

if it is a knocking noise that is varying with road speed, start with a quick check round the wheel bolts. then check:

tyres - deformed tyre, or something stuck in the tyre that is fouling something. stone or similar stuck in the tread
jack it up and spin the wheels by hand. feel for any rough / tight spots.
check nothing has come adrift and is fouling on the driveshafts
grab hold of the 'ears' on the gearbox where the driveshafts bolt on and give them a wiggle. check for up/down or fore/aft play that would indicate diff bearing problems


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Jimbob
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Re: Knocking/Tapping speeds up on acceleration....any ideas??

Post by Jimbob »

thanks for the swift responses fellas :good:

I'll work through those checkups next chance I get.

The thing that's making me most concerned is that the noise only occurs when the car is moving and importantly foot is on the gas. ie There is no sound when just cruising or braking.

I know that the front two tyres are on their way out,both wearing on the inside,( think I need to get it braced from underneath) wouldn't have thought that should cause this noise having said that.

did notice it was worse cornering to the left actually as well so possibly something fouling on just one side...


Nate
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Re: Knocking/Tapping speeds up on acceleration....any ideas??

Post by Nate »

[quote="Jimbob"I know that the front two tyres are on their way out,both wearing on the inside,( think I need to get it braced from underneath)[/quote]

tyres wearing on the inside edge would suggest that the tracking is excessively toeing out.
Jimbob wrote:did notice it was worse cornering to the left actually as well so possibly something fouling on just one side...
this would suggest possible wheel bearing problem. turning one way loads up the bearing and alters the noise


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Funky Diver
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Re: Knocking/Tapping speeds up on acceleration....any ideas??

Post by Funky Diver »

and front bearings are a bugger... I'm gonna get mine done by someone with the gubbins when I strip that part of the car out just to be on the safe side!


Jimbob
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Re: Knocking/Tapping speeds up on acceleration....any ideas??

Post by Jimbob »

Ok so just had the problem diagnosed and fixed up by my(quickly becoming legendary) local mechanic today, back on the road...for now... :chill:

If your wondering it turned out to be a knackered CV joint, drivers side, both inside and outside..


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