Knocking/vibrating sound on 172cup

[CuppyDean]

Hi guys,
Just wondered if anyone could help me out with a slight problem i have on my 172 cup, when accelerating quite hard in 1st theres a knocking/vibrating sound which comes in around 4k revs and lasts till about 5k revs then it stops, it happens ever so slightly when changing into 2nd but every gear after that then its completely fine, under normal driving its absolutely fine, from what i can hear it sounds like its coming from under the car sort of dash board area, i have had the exhaust heat shield checked today and that seems all fine, this problem only happened a week or so ago and only noticed it when i gave it some in 1st, the cam/aux belt has just recently been changed to but i gave it some when it just got changed and it seemed fine so im thinking it shouldnt be this, so im stuck really on what it could be, any help would be much appreciated

Thanks in advance

 

[richo]

http://www.cliosport.net/forum/showthread.php?t=448443&highlight=cup+knocking

Should help mate

 

[CuppyDean]

http://www.cliosport.net/forum/showthread.php?t=448443&highlight=cup+knocking

Should help mate

Thanks i was thinking its could be the engine mounts, after reading that post then im sure 100% is it the engine mounts. What happens if i just leave the existing engine mounts? any dangers?

Thanks

 

[Jonff]

The knocking/vibrating just gets worse and worse over time, can't imagine it'll do it any good to just leave it though. I've replaced 3 of the 4 of mine up to now.

 

[CuppyDean]

Have you replace yours with the ktec uprated ones or just normal renault ones? had a look at the ktec mounts and there quite expensive, is there a quick fix to this problem or do i have to bite the bullet and buy ktecs uprated ones

 

[Jonff]

I went with the standard mounts from Renault and used powerflex mounts in my lower engine mount (dogbone mount). In the long run it's probably better to go for the more expensive k-tec mounts because they'll last longer. If you do though be prepared for extra cabin vibrations.

 

[CuppyDean]

I went with the standard mounts from Renault and used powerflex mounts in my lower engine mount (dogbone mount). In the long run it's probably better to go for the more expensive k-tec mounts because they'll last longer. If you do though be prepared for extra cabin vibrations.

Oh god i dont want extra cabin vibrations i want no vibrations lol so is the lower engine mount the dogbone mount which is the one which causes the problem? Are the renault mounts expensive to buy and install?

Many thanks

 

[Jonff]

Oh god i dont want extra cabin vibrations i want no vibrations lol so is the lower engine mount the dogbone mount which is the one which causes the problem? Are the renault mounts expensive to buy and install?

Many thanks

If you have a search around the site for "uprated k-tec engine mounts" you'll be able to view other people's opinions of them. The powerflex mounts I've got in mine cause more alot of vibration in the cabin on idle but it doesn't bother me.

Does the gearstick waggle about when you're booting it? if so it'll be the dogbone mount that's the problem. Mine was the upper engine mount causing the problem (the one that's visable on the drivers side when you look in the engine bay) then the upper gearbox mount gave up (sits under the battery).

Cheapest place I've found for the standard engine mounts are EuroCarParts. Can't remember prices off the top of my head but you'll have to ring them or actually go in because their website is useless and doesn't list them.

 

[CuppyDean]

If you have a search around the site for "uprated k-tec engine mounts" you'll be able to view other people's opinions of them. The powerflex mounts I've got in mine cause more alot of vibration in the cabin on idle but it doesn't bother me.

Does the gearstick waggle about when you're booting it? if so it'll be the dogbone mount that's the problem. Mine was the upper engine mount causing the problem (the one that's visable on the drivers side when you look in the engine bay) then the upper gearbox mount gave up (sits under the battery).

Cheapest place I've found for the standard engine mounts are EuroCarParts. Can't remember prices off the top of my head but you'll have to ring them or actually go in because their website is useless and doesn't list them.

If i can remember when giving it some the gear stick doesnt waggle at all, and even when idling the car is silent with no vibration, so it must be the top engine mounts then, are the engine mounts a reanult job or a diy job?

Thanks

 

[Jonff]

If i can remember when giving it some the gear stick doesnt waggle at all, and even when idling the car is silent with no vibration, so it must be the top engine mounts then, are the engine mounts a reanult job or a diy job?

Thanks

I did mine myself, pretty easy really.

 

[CuppyDean]

I did mine myself, pretty easy really.

Ive been reading a few reviews on here for the ktec uprated mounts, there are some big positives but the negative what would irratate me is the cabin vibration, i just done want my car to feel ilike a washing machine lol are you currently using the powerflex bushes with the original renault mounts? and are they any better?

Cheers