172 Cup clunk clonk

[ex-Chinese Dave]

Noticed this the other day....from the drivers front area, if I come off the gas quickly at low speed there is a clunk/clonk noise, but it doesn't do it all the time. All the suspension bits are newish, wheels are on correctly, no issues with braking etc and it only does it as described. I've driven left and right at full lock and there is not a peep. I was thinking it' could be a driveshaft issue but that would happen all the time, right? The only other thing is the top mounts, which are also newish and OEM parts, because we all know that top mounts can be a b*stard bag of sh1te from time to time. And this is not my other clonk that i've posted about.

Any ideas as to what it could be?

 

[Myfanwyi Saunfire]

Not this kind of clunk clonk is it?

 

[ex-Chinese Dave]

No, it's just a single clunk as I come off the gas.

 

[mumpy]

Noticed this the other day....from the drivers front area, if I come off the gas quickly at low speed there is a clunk/clonk noise, but it doesn't do it all the time. All the suspension bits are newish, wheels are on correctly, no issues with braking etc and it only does it as described. I've driven left and right at full lock and there is not a peep. I was thinking it' could be a driveshaft issue but that would happen all the time, right? The only other thing is the top mounts, which are also newish and OEM parts, because we all know that top mounts can be a b*stard bag of sh1te from time to time. And this is not my other clonk that i've posted about.

Any ideas as to what it could be?

Mine was doing something very similar, check your top engine mount

 

[ex-Chinese Dave]

That is also new, but i'll check it.

 

[Myfanwyi Saunfire]

No, it's just a single clunk as I come off the gas.

You can rule driveshaft out then.

As Mumpy says, probably engine mount or dogbone mount.
If the lower one goes then the manifold can catch the subframe and cause a clunk.

 

[andybond]

Does it only do it when dry? My nearside clonked at low speed and when using large lock. I stuck on a small amount of silicon grease and it went away ...

 

[ex-Chinese Dave]

It's only done it the last few days so mostly in the damp. My dogbone is also newish and i'm certain it's coming from the front right, not underneath.

 

[mumpy]

It's only done it the last few days so mostly in the damp. My dogbone is also newish and i'm certain it's coming from the front right, not underneath.

I have relatively newish Vibra technics mounts and the top nut had worked itself loose on the top engine mount

 

[ex-Chinese Dave]

I'll be checking it today. For those that know it may be my pigeon🤣

 

[ex-Chinese Dave]

Right, I just checked the top engine mount using a standard extension coupled with a half extension from my socket set. Just with that I was able to put about a quarter of a turn on all five of the bolts
/nut. I’ve tightened them as much as I can without swinging on the bar and so let’s see if they were the cause of the knocking. I’m guessing it wouldn’t take much to make a noise if those bolts/nut were slightly loose. I’ll keep an eye on them over the next few months and get them torqued up correctly when it goes for its next service.

 

[Matt Cup]

Torque specs for those bolts along with a load more are here just so you don’t over do them.

172/182 Torque Wrench Settings

Can we progressively populate this guide with torque wrench settings so we have a one stop place for all know torque settings: Engine Inlet Pulley (dephaser): 100nm (Fred does them to 125nm as he doesn't trust it) Exhaust Pulley: 30nm + 86deg (that normally equates to 125nm) Idlers: 55nm...

cliosport.net

 

[Clio_fool]

My 200 makes a similar noise occasionally, maybe I should fit the new engine mounts I have laying about somewhere.