AAZ cutting out after motorway driving

[airhead]

My AAZ engine cuts out if I pull up to a roundabout or a set of traffic lights after a bout of sustained motorway driving. It's pretty damn annoying cause it won't bump start when I let my foot off the clutch again. I was thinking it may be because the intake is quite low down and could be pulling in hot air from around the manifold and turbo and it chokes up when it's to run at idle suddenly. It's a sort of K&N filter on the engine which is on the end of a pipe thats down the left side of the engine. Is this likely or is there anything else that could be causing it?

[airhead]

Anyone??