Lumpy idle and bogs down at 4000rpm

Subject says it all really ...

1996 IL4 Zetec /Std Tranny

New Plugs/Wires
Fuel Pressure is around 38psi (42psi with regultaor disconnected)
No apparent vacuum leaks
IAC cleaned (not checked resistance yet tho)

The idle is a little lumpy almost stalling at times
Under hard acceleration it bogs down around 4000rpm if you use half throttle it seems fine all the way to the redline

Exhaust doesn't seem restricted , any ideas?


Thanks

fuel pump and filter couldnt hurt to be changed.

I've changed the Fuel Filter earlierin the week, it made no difference and i can't see it being the pump if the pressure is good