Hello - I have a 1992 V12 Vanden Plas (Series 3). The AAV was making a very loud whistling noise and the car has been running a bit rough when hot.
I bought a new Lucas brand AAV, listed for my car with the 5.3 litre. The new AAV has a much smaller orifice than the original one (seen here.) I know the one I took off either factory or dealer installed, as my car has 39,000 km on it and the gasket material was the dark red paper that Jaguar use to use.
As expected, when cold the engine will not idle unless I open the throttle a bit and when it’s warm, I had to crank out the adjustment screw on the AAV to get 650 rpm. Even with the screw out, it will not idle when cold.
Did I get the wrong AAV? How can I ensure I get the correct part number next time?
Can I make up for the smaller orifice on the new AAV by setting the throttles a bit more open at idle?