absolutly invisible rattle noise from 4K rpm

[richleeson]

hi all, ive got the craziest rattle noise ever! ive had it for a couple of weeks now its starts from 4K upwards and sounds just like a loose heatshield, it started happening after i had my cambelt done.

if youve got your head in the engine bay you cant really notice it but if you stand at the side of the car its very noticable it sounds to me like its coming from the rear lower section/drivers section of the engine bay but its very difficult to tell exactly where

ive removed the full exhaust system and checked for loose baffles and had the flanges welded all the way round instead of spot welded.

ive took all the plastic tray off and took the drivers wheel off and had a good poke around and watched it while it is doing it.

ive checked all heat shields and brackets that i can see.

ive had it on a proper ramp whilst 3 people stood underneath it whilst it was making the noise and they could find anything.

i really dont know where to go next.... any ideas.... the car drives absolutly fine its purely just a damn annoying noise wich makes it sound like a right nail!

any help would be much appreciated!!

edit: the car is an evo 8 260

 

[B6lee]

auxillery belt tensioner i expect

 

[richleeson]

oo funny you should say that as it started happening right after i had the aux belt changed!(had cam and aux done at same time),is the tensioner simple to replace?
thanks for the reply

 

[richleeson]

think i might let the engine heat up, remove the belt and then very quickly rev the engine to see if the noise still occurs and go from there! im sure it wont cause a problem aslong as im quick!

 

[B6lee]

just release the tension with a 1/2 inch square drive and lock it in that position with a thin screwdriver. then undo 1no 12mm & 1no 14mm bolt. job done

 

[richleeson]

nice sounds easy peasy! their £120 on camskill tho! :-o will ring evo breakers!

 

[B6lee]

good call

 

[richleeson]

just whipped the tensioner off to have a look and there is play in the bearing, theres a few bearing places by me so i might see if i can just get the bearing and replace it. hopefully be able to get one tomoz! there is play in the power steering pulley aswell but it doesnt sound like the noise is coming from there..... we shall see!

 

[B6lee]

Ah nice one.
They are common to make strange rattle noise. Seems to happen after cambelt has been changed

 

[fq-craigus]

i think i have the strange noise too, and my cambelt was changed when i rebuilt. sounds like its coming from under the car though its a strange one

 

[B6lee]

Can sometimes be heard when pulling away

 

[fq-craigus]

i only hear it at around 3.5 to 4k it does sound like exhaust but its not touching anthing all mounts r on and all nice and tight

 

[B6lee]

Check the tensioner then Craig.

 

[fq-craigus]

its like a reverberating kind of noise

 

[B6lee]

If the exhaust isn't touching the under braces then yea I'd say tensioner. My mates V was making the same weird noise after i did cambelt and sure enough was the tensioner.
Also a couple people been on here with same issue after a belt change.

 

[fq-craigus]

will do, might even take it along to autotorque im fed up of trying to work on the car in the street in the rain lol

 

[richleeson]

craig your noise sounds like its exactly the same as mine, mine also sounds like its under the car too.... if i can get a bearing tomoz ill let ya know asap if it fixes it.

 

[fq-craigus]

cheers buddy, i might even make a quick video in a while so there is a refrence for future maybe, its bloody annoying.

 

[richleeson]

it didnt work!! still exactly the same noise, im fed up now im throwing the towel in...... im gonna do the last thing that any of us ever want to do...... im gonna take it.......... to a dealers!!! :disgusted: this is a sad day indeed!

 

[richleeson]

just been reading on the internet and someone said they had a similar rattle to mine and in the end it was due to a balancer shaft being out of time..... does this sound feasable? i dont know anything about balancer shafts! but seen as its started happening after the cam and balancer shaft belt has been changed its got me wondering??? could anyone shed any light on this for me??