Odd rattle

[stevesey]

Anyone had anything like this before?

Noticed a faint rattle over the past couple days. Rattle is not road/engine speed dependent, just a constant faint "crackle" (for want of a better description) that you can't really pin-point from inside the car. As you slow down the noise remains the same (in volume and frequency) until you actually come to halt (when it stops). Noticed this morning that when parking that if you switch from D -> N -> R -> N -> D the rattle occurs for about 2 seconds on engaging D or N then goes quiet until you lift of the brake and start moving.

Can't out what sort of thing would fit these symptoms. Although having sat down to explain it, it crosses my mind to see if it's coming from the PCV (probably a similar frequency to the PCV ticking noise) - that might explain the fact that it's constant noise and perhaps the act of engaging D/R causes a blip in engine speed/vaccum resulting in the 2 second burst (although the PCV nromally carries on ticking at idle).

Wondered if anyone had come across similar (the short burst when engaging D/R ought to be pretty unique).

 

[BlackC55]

Are the CATS ok?

 

[stevesey]

I hope so!!! If it was CATs won't the noise vary with engine load (and be more noticeable with the door open)?

 

[BlackC55]

Yes probably.

Its difficult to say without hearing it. Can you record it?

 

[stevesey]

Might be worth a try, but it isn't very loud so might get swamped by microphone hiss (might be easier to pin point if was louder). Was only just noticeable before getting on the motorway tonight 5 miles, then after 25 miles of motorway I couldn't hear it between motorway and home (this morning it was quiet leaving home, but I could hear it coming off the motorway at the work end).

If I can capture any sound I'll post a link.