Hi Guys,
I need your expert help
A mystery knocking noise has appeared on my 2006 1.4 2 door Grande Punto (77k miles) which seems to be coming from the rear which has me puzzled and doesn't sound like any forum threads I've searched.
Firstly the car passed it's MOT on 31 October 2020 with no advisories so I'm assuming all important bits underneath were ok then.
Since then I've probably done 75 miles and I use it 2-3 times a week. I am in London in a speedhump area but don't do any break neck speed over them.
When the noise first appeared it sounded like a very gentle scrape with a knock at a certain point in time which would go on for a random length then stop - then start for a random length then stop - but we're talking just 3-10 seconds. The best I can describe it is if you stuck a playing card to a wheel and spun it, the card would make a noise each time it hit the frame at the same interval. It sounded rotational.
It would happen randomly for a varying length of time just once or twice during a drive.
There was no pattern when it would happen - accelerating, braking, turning or going over a speedhump.
Then it seems to have turned into more of a knock or just got a bit louder but is happening more often.
Today I removed the parcel shelf and went on a 4 mile return trip.
I'm certain it's coming from the rear as it's louder with parcel shelf removed and empty boot.
It still seems quite random but now more often. It also happens while driving slowly (20mph) on a good flat road.
No pattern going over speedhumps or rough patches of road.
The noise happened while going up/downhill, coasting, changing gear at 20-30mph.
I have given my exhaust the shake test by grabbing the pipe at the back and shaking it by hand - no knocking.
Manually bumping each corner doesn't present anything out of the ordinary.
The only thing I have done is got a replacement tyre and rotated them around 3 weeks ago. All tyres are the same 175/65/R15.
My drivers side rear tyre was replaced with a very good part worn - same make and type as the other side.
I put the rears swapping them diagonally to front (passenger side rear tyre to drivers front - replacement tyre to passengers front)
And the front tyres on the same sides to the rear.
If anything I would expect just some tyre noise after rotating them not any knocking noise - unless during the process I have done something which introduced the issue.
I'm planning on jacking up the car tomorrow to take a good look under the rear, front and check all wheel bearings.
Any suggestions would be greatly appreciated
BTW: Is it easy to access the rear strut top mounts or lots of disassembly?
Thanks.
UPDATE:
I have checked all wheel bearings which seem fine - no wheel wobble or play in them.
All wheels spin freely - the passenger rear wheel has a bit of brake grip as it doesn't freewheel all the way to a stop but sometimes just stops about 2 seconds before the opposite side would.
I have done a heavy duty bounce test with me standing on the door sill and holding the internal hand grip then bouncing around - the drivers rear side does have a creak. Visual inspection up the strut both look ok and nothing out-of-place on the visible lower part of the mount.
The springs look ok as do both lower bushes - they look aged but complete and again nothing out-of-place.
The drop links don't have any play in them and the passenger side one is nice shiny silver so must be a replacement.
I took it up/down the road at 40mph and didn't hear the noise
I need your expert help
A mystery knocking noise has appeared on my 2006 1.4 2 door Grande Punto (77k miles) which seems to be coming from the rear which has me puzzled and doesn't sound like any forum threads I've searched.
Firstly the car passed it's MOT on 31 October 2020 with no advisories so I'm assuming all important bits underneath were ok then.
Since then I've probably done 75 miles and I use it 2-3 times a week. I am in London in a speedhump area but don't do any break neck speed over them.
When the noise first appeared it sounded like a very gentle scrape with a knock at a certain point in time which would go on for a random length then stop - then start for a random length then stop - but we're talking just 3-10 seconds. The best I can describe it is if you stuck a playing card to a wheel and spun it, the card would make a noise each time it hit the frame at the same interval. It sounded rotational.
It would happen randomly for a varying length of time just once or twice during a drive.
There was no pattern when it would happen - accelerating, braking, turning or going over a speedhump.
Then it seems to have turned into more of a knock or just got a bit louder but is happening more often.
Today I removed the parcel shelf and went on a 4 mile return trip.
I'm certain it's coming from the rear as it's louder with parcel shelf removed and empty boot.
It still seems quite random but now more often. It also happens while driving slowly (20mph) on a good flat road.
No pattern going over speedhumps or rough patches of road.
The noise happened while going up/downhill, coasting, changing gear at 20-30mph.
I have given my exhaust the shake test by grabbing the pipe at the back and shaking it by hand - no knocking.
Manually bumping each corner doesn't present anything out of the ordinary.
The only thing I have done is got a replacement tyre and rotated them around 3 weeks ago. All tyres are the same 175/65/R15.
My drivers side rear tyre was replaced with a very good part worn - same make and type as the other side.
I put the rears swapping them diagonally to front (passenger side rear tyre to drivers front - replacement tyre to passengers front)
And the front tyres on the same sides to the rear.
If anything I would expect just some tyre noise after rotating them not any knocking noise - unless during the process I have done something which introduced the issue.
I'm planning on jacking up the car tomorrow to take a good look under the rear, front and check all wheel bearings.
Any suggestions would be greatly appreciated
BTW: Is it easy to access the rear strut top mounts or lots of disassembly?
Thanks.
UPDATE:
I have checked all wheel bearings which seem fine - no wheel wobble or play in them.
All wheels spin freely - the passenger rear wheel has a bit of brake grip as it doesn't freewheel all the way to a stop but sometimes just stops about 2 seconds before the opposite side would.
I have done a heavy duty bounce test with me standing on the door sill and holding the internal hand grip then bouncing around - the drivers rear side does have a creak. Visual inspection up the strut both look ok and nothing out-of-place on the visible lower part of the mount.
The springs look ok as do both lower bushes - they look aged but complete and again nothing out-of-place.
The drop links don't have any play in them and the passenger side one is nice shiny silver so must be a replacement.
I took it up/down the road at 40mph and didn't hear the noise
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