Clio 172 strange noise

[xoldog400]

Hi, a friend of mine has also a sport 172, so he is concerned with some strange noise.
you can hear it when the car is in neutral position, when the temp needle is in the middle (warmed up) the sound can't be heard inside of the car, only outside. it's like a sik-sik-sik-sik sound (something like a sewing machine sound?) and it follows the rythm of the machine. he also uses motul x-cess 5w40 (normal consumption)
so what could it be? - the heatshield is ok, maybe the cat or something in the machine although the sound is more coming from the position of the cat?
if anyone has any idea...

 

[Finny]

mine sounded bad for a while and found the centre section had collapsed or something inside might be something on the lines of that or something as simple as a bolt come loose maybe worth getting it up on a ramp and give it a good look over before he chucks loads into it! i may be corrected but just things ive found on cars ive had bud

 

[xoldog400]

he has a original cat (the car has 150.000 km), and a new center pipe + rear silencer. the heatshiled is completely checked...maybe the part of the heatshield beneath the manifold?
as i said the noise is like "sik-sik-sik-sik" (sewing-machine kinda sound) and it is coming from the area of the cat, and it can be heard only when the car is warmed up to working temp.
only in neutral, when you rev it it dissapears.

 

[Bramley]

I bet its the pulley or around there

 

[xoldog400]

you think that a pulley could sound like that...but wouldn't it be present when the car is cold too?

 

[Fred@BTM]

will either be the carbon canister behind the wheel arch, easy to check, unhook the vaccum line and block it off, if the noise goes its the canister

could be the dephaser, or possibly the water pump (rare)

if it only does it when the car is hot, then i'd say dephaser = £650

 

[xoldog400]

ok, will tell him to check the canister...fred with this price (650) you mean dephaser+belts+tensioners.
it's not that loud, he's having that noise since he bought the car (3 years), as i said i reminds on a sewing machine ticking

 

[xoldog400]

fred or others...if it's no problem could you please with a picture show this carbon canister.
thanks in advance!

 

[Fred@BTM]

if its just a faint "tap, tap, tap, tap, tap" then it'll probably be the carbon canister, disconnect the vaccum line to the left hand side of the plenum and put your finger over the hose on the engine

 

[xoldog400]

ok, fred but this sounds like "sik-sik-sik-sik" some kinda sikting sound.

 

[Fred@BTM]

get a video

 

[xoldog400]

sorry guys i was wrong, today i drived his car and we he was warmed up it had that sik-sik-sik-sik noise on idle and when you rev it the noise also speeds up.
as i said only warmed up.

 

[xoldog400]

now can't get the video but heard it today again...as i said only on idle, the noise isn't coming from any area of the engine/cover. it can only be heard on the drivers side (only outside the car), somewhere in position of cat, front wheel, can't position it directly.
it's a "tok-tok,tok-tok-tok,tok-tok" sound (one hit, two hits, one...if you get me) not to loud