V6: Ticking noise - need to identify the component

[8Jb9]

First a short history of the car:
[*] In December I had an rpm-sensor (TDC-sensor?) replaced because the car didn't start
[*] Just now I had the right drive shaft replaced, after it had failed under load (covered in a different thread).

Now that I got it back it has - only sometimes - ticked loudly from the engine compartment. Not audible inside the car, but most certainly so outside. The ticking increases with engine rpm. When idling the ticking noise has a rate of maybe 2-3Hz. I can't feel anything alarming with how the car behaves - the power is delivered the way I expect it to, and the engine appears to run smoothly.

When holding my fingers on the highlighted tube in the picture (right side of the car) I can "feel" the ticks. Can't feel it if I place my hand on the computer box next to it or the engine itself.

So, my question is: what is that tube connected to - what is it that is ticking? And is it serious?

[lozz]

Its something to do with the emisions system..not sure of the correct terms, purge valve or summat iirc,
My 306 has one and makes a faint ticking noise, so ipresume its Norm on pugs

[lozz]

Just checked in a old book ive got

its a Purge valve -emisions control unit,

iwouidnt worry about the ticking

[8Jb9]

Thanks a lot - your first post led me to a good explanation of how that system works.

I'll sleep better tonight :-)

[lozz]

all the noise is,

theres metal discs inside,of which rattle with age,

i took one apart on arenault and tightend the screw and the ticking stopped,
its hardly worth worying about alot of french cars have them and they tick just like egr solenoids and others do etc.

the one on the 306 ive got iput a rag round it and gave it a tap its gone quietish now, was going to take it apart or replace it
but once the bonnet is shut you dont hear it so not worth messing with ithought