1.9 TDI noise

[Nae gear]

Hi All.
It's taken me ages to find my way in here, I hope it's the right place to find a fix for a noise in my 2000 A4 TDI???
The said noise is coming from the diaphram on top of the mechanical EGR valve, ( on air minifold). It sounds like the diaphram is pulling and releasing about twice per second at tickover causing a flapping kind of noise. It happens most days and usually only lasts for 5 or 6 seconds at a time, performance is not affected, but I'm worried something is about to go.
Hope someones heard same noise.
Kind regards.

[Crasher]

That is a very odd problem, has it generated a fault code?

[Nae gear]

Sorry for the delay, I've got less o' a clue here tham i have wi ma Audi.
Never had it checked (too tight wl money) The noise stopes if I unplug other EGR valve (not the mechanical one) and when I remove vaccuum pipe.

[wadi110]

Hi Mate Is Yours The 1.9 Tdi Ajm Engine? If So Change The Charge Pressure Switch Located Near The Diesel Filter Next Too The Engine Coolant Bottel 99.9% Thant Your Problem Its Cost About £45 for pressure switch.


thanks

[Nae gear]

Hi, It is an AJM engine, I know the part you mean, think it's another EGR valve ( not mechanical one) I had it shoved to the side during a clutch change bout a month ago.
What triggers or adjusts it?? I dont know of any Lambda sensor and dont see anythin to check exhaust gasses. Any problrm in unplugging it until I replace it??

[wadi110]

By Unplugging It You Will Also Lose Power. I Would Buy The New One First And Then REmove Too Replace

[Nae gear]

Thanks for that. It's just dawned on me that there are two sensorsi n that area by the oil filter, one in the top of the air intake duct, and the one I think you mean, fixed under (not in) the air intake duct and has three wee pipes coming from it.
Have I got the right one??

[wadi110]

yes mate the one under the intake pipe is the correct one.

[Nae gear]

Many thanks for your help, the wife says theres been no noise for last two days. I'll let you know when it's resolved.
Best regards.

[Nae gear]

Final update,
I replaced the part you suggested. Audi call it a pressure converter Pt. No 1J0 906 627 and all is now well. Many thanks VADi110 I hope you get notification of this.

A' the best :beerchug: