Metal Vibration / Rattle at high revs / deceleration

[bearne1]

Hi all,

I have recently developed a loud rattling noise from what I assume is under the car during higher revs and at deceleration, again at various speeds.

Had my MOT yesterday and had a look under the car and no apparent problems with the heatshields or exhaust (Janspeed full system), the rear shield recently secured with larger washers, and all the mounts / joints have been replaced by Protyre in the last 12 months.

Does this sound more like a Cat failure or one that is imminent?

Thanks

Daniel

 

[bearne1]

Have had the exhaust / heat shields checked and slight adjustments and still the noise remains at certain rev ranges.

May be just my car OCD but would like to get to the bottom of this, have suggestions of worn engine mounts or possible clutch fault, any ideas guys?

 

[imprezaworks]

Hard to tell over the interwebz. Exhaust catching the gear selector?

 

[SWL16]

Long shot for a 'rattling noise' but...How close to your exhaust trim is your exhaust?

I had a problem with my janspeed moving a lot vertically under lift off and catching the trim. Re aligned with a cable tied bolt in the mount. Never had the problem again.

 

[bearne1]

Yes have had this problem in the past but the backbox sits perfectly now after fitting the Powerflex rear mounts. This move vibrates and you can hear the plastic, but this is more of a metallic rattle / vibration.

 

[imprezaworks]

Heat shield probably

 

[bearne1]

Think I may try and adjust the engine mount slightly as that is the only thing I can think of at the moment but yes have a sneaky suspicion it is a heatshield, more likely to be one behind the bulkhead?

 

[MicKPM]

Heat shield or Manifold to CAT seal spring kit has pulled thru. You're gonna have to get under her i'm afraid.

 

[bearne1]

Thanks for the replies.

Noticed this evening that the vibration is present when car is sat idle in neutral and revving it hard so hopefully this eliminates any suspect clutch problem.

The manifold to cat joint had the whole kit replaced last year using Renault parts.

 

[realnumber 1]

Fuel rail guard possibly? Vibrations/sounds can travel sometimes..

 

[bearne1]

Will check the guard later, one thing I have noticed this morning is the noise only seems to rattle when the car is at full running temperature which leads me to thinking it may be the cat (have had the emisions light on a few times in the last month) ?

 

[imprezaworks]

Quite possibly. Or the shield will rattle when hot.

 

[bearne1]

Quite possibly. Or the shield will rattle when hot.

Which shield do you think is most likely?

 

[imprezaworks]

http://www.cliosport.net/threads/exhaust-heat-sheild-rattle-can-i-remove-it.513584/

 

[bearne1]

Might be worth a try, I fitted larger washers last year and thought I had cured the rear end, it sounds more like its coming from the front. Will pop to Protyre at lunch today and see if they can find out what the problem is.

 

[bearne1]

Appears to be no external objects or shield in contact with the exhaust and hangers all in good order after a visit to Protyre. Must therefore assume the problems lies inside the Cat or the exhaust system itself. Have not seen any horror stories with Janspeed system failing so assume my best bet is to look at replacing the cat?

 

[imprezaworks]

Decat time

 

[bearne1]

Yes very tempted for the first time since ownership, where is the best place to source a replacement OEM cat, otherwise I shall go for the Janspeed decat to match the exhaust!

 

[imprezaworks]

Get one off here? Think they are mega new for a genuine. Could be wrong though.

@cs_dave for second hand or decat for real men

 

[K_McDermott]

Was just about to make this exact thread!!!

Manifold to cat springs! *goes to get jack out the garage


Sent from my iPhone using Tapatalk

 

[cs_dave]

Baffles in the centre silencer is a possible rattle

 

[bearne1]

Fuel rail guard possibly? Vibrations/sounds can travel sometimes..

This was indeed loose but not the cause, good shout!

 

[bearne1]

Baffles in the centre silencer is a possible rattle

It is either this or the cat so going to try replacing the cat first and see if the centre section (Janspeed) shows any signs of damage when it is removed.

 

[bearne1]

I managed to source a new cat going on tomorrow with the cat mod to match the 2.25" mid section, but after a day of tinkering yesterday the noise has gone. I can put it down to a clip which holds 2 heat Shields together, or a bolt which was loose in the throttle bottle, very odd!

 

[K_McDermott]

Checked mine was the cat to manifold bolt, the s**t one to get at on the drivers side, can't even retughten as the nuts stripped on the threads


Sent from my iPhone using Tapatalk

 

[bearne1]

Checked mine was the cat to manifold bolt, the s**t one to get at on the drivers side, can't even retughten as the nuts stripped on the threads


Sent from my iPhone using Tapatalk

Common problem but I had a genuine kit fitted last year and the springs look good and tight. Still it'll all be off tomorrow for the new cat and retightened and checked for any leaks. A new cat probably isn't needed but may as well get it on given its brand spanking.

 

[M.C..]

I had a rattle a few years ago under hard acceleration and it was the rear exhaust hanger catching the aluminium mount.

 

[bearne1]

After having the new cat fitted the car runs and pulls nicely bit still have this intermittent rattle / vibration!

I have noticed one of the cat to manifold springs is loser on one side, the kit wasn't replaced that long ago but could this be a possible cause?

 

[K_McDermott]

After having the new cat fitted the car runs and pulls nicely bit still have this intermittent rattle / vibration!

I have noticed one of the cat to manifold springs is loser on one side, the kit wasn't replaced that long ago but could this be a possible cause?

If it's loose it will rattle mate, best off tightening both up as much as possible then seeing if it's still got a rattle



Sent from my iPhone using Tapatalk

 

[bearne1]

If it's loose it will rattle mate, best off tightening both up as much as possible then seeing if it's still got a rattle

The loose side will not tighten up anymore. I have done almost everything now and nothing is fouling the exhaust, decent clearance near the ARB so will try another cat to manifold kit. One spring set is solid on one side, does the springs loose tension or is it more to do with the washers / bolt itself?

 

[bearne1]

So after solid exhaust mounts, new centre mount, new donut gasket between cat and manifold, new cat and weld mod to match exhaust diameter, engine mounts, Evol dogbone mount and all hestshield clips the rattle continued until.....replacement Janspeed centre section.

Went for the unsilenced section over silenced which I've had on the car since 2009, and the noise difference is marginal without a decat. So, so pleased this has finally cured the pain of wondering and the expense!

 

[bearne1]

Baffles in the centre silencer is a possible rattle

Winner awarded to you!

 

[cs_dave]

Winner awarded to you!

Glad it's sorted tho mate