KA stalling

anyone come across this one ....

when engine is rev'd to greater than 3000 rpm it stalls as revs die down (Hot fuel smell when restated)

less than 3000 rpm engine returns to idle OK

I've cleaned out the idle control valve with no effect

I've also got 2 fault codes ...

1479 high fan ctrl pri circ

I've zero'ed both but they re-occur

Emissions are negligible so strangley enough the CAT is either OK or

(I suspect) never did anything anyway !

Any help appreciated.

CheeRS