Scirocco Register

I've been struggling to resolve a problem with my daily - it's a J plate Scala on *just* 185k miles. There's a hissing noise like an air leak, but I've had the inlet manifold off recently, with a new gasket, and there were no obvious signs of cracks or other damage.

I had a listen the other day down a cardboard tube, to try and narrow down where the noise was coming from, and I think it's the aux air valve. I tried another one, but that didn't seem to make any difference.

I'm assuming it's an air leak into the engine, but is it possible to have a hissing noise from the joint in the toilet bowl manifold? Sounds more like an inlet vacuum hiss to me though, rather than pulsing like an exhaust leak.

mike has it got the air valve thing on the back of the head ? its inline with injector 3 & 4. The plastic casing could be damaged.

Hi Jake - it's a digifant head, so it hasn't got that bit, and the end of the pipe is not open (piped to a 16v WUR).

The holy cardboard tube of wisdom says it's the AAV. I might see if I can bridge the hose connections and see if it stops it.

Does yours run on Kjet? Has it still got the AAV, or does it have the 16v ISV setup?