hissing noise

It is a 2007 A5 (136k miles) with the 3.0 TDI capa engine I'm now noticing a strong diesel smell accompanied by a louder rattling as I chug along slowly I had noticed a small rattle from the timing chain before but nothing concerning tbh. I took off my oil cap today when cold and noticed a...

2006 A3 2.0T fsi. So I’ve got a weird hissing noise and it’s NOT when I’m accelerating... It only happens above around 20mph, in gear and with no feet on the pedals. As soon as I touch the accelerator, even slightly it goes away. The hiss also goes away when I press the clutch in. I cannot find...

Hi Wonder if anyone can help ? I have a AudiQ7 2010 3.0 Sline Past couple of days I have started hearing a hissing / bubbling noise from around the passenger foot well or behind glove box. This can be heard when the car is running and continues for around 30 seconds when the engine is switched...