Strange noise ....any ideas ?

[Blue Two]

New Valve, rubber mounted solenoid - still no joy!

ARRG!

I've got the typical deep bass-y honking noise coming from my A2 TDi, I have replaced the EGR valve along with the gas inlet pipe from the exhaust manifold (parts fella at Slough Audi said to change that too). In light of the 'official' modification I've rubber mounted my solenoid valve assembly using two 1/2 tap washers! BUT, I've still got noise on part throttle whether under load or not although it doesn't boom through the dashboard as before.

I've listened very, very carefully whilst the rev's are 'blipped' just off idle and the noise appears to be eminating from the EGR valve itself, like the diagphram is making the noise. Before I throw in the towel and disconnect the valve, is there anything ELSE I can try?

Cheers.

Mike

 

[Blue Two]

I meant to say two 1/2 inch rubber tap washers, sorry. They fit snugly on the stud and are about 3mm thick allowing plenty of thread to remain.

Any ideas why the noise only happens when the car is hot?

Thanks.

 

[Imartin]

Mooing noise - EGR valve

Our TDI has developed the common mooing noise. Did some fault diagnosis myself and tracked the source of the noise to the EGR valve. On top of the valve assembly appears to be the mechanism that operates the valve. Connected to the valve is a vacuum pipe. I disconnected and blanked the pipe and went for a drive. No more mooing. I expect the assembly on the valve houses a diaphragm which possibly has a hole in it. The noise must be generated by air being sucked through the diaphragm. Audi test this part by putting a vacuum pump onto the valve to check its operation. This function I will have to check before going for a replacement. Maybe even removing it and giving it a good clean out might help.
The Audi manual also states that the EGR valve only operates for the first 2 minutes after start up and is then switced off by the ECU.
Have left the pipe disconnected for now.

 

[spartacus 68]

My wife got her A2 fixed under warranty last year. Audi mechanic was 'very much aware of the problem' and said it was an A2 trait. They fitted the upgraded rubber EGR mount. I still hear it - but have learnt to live with it.