right this is doing my head in now

since day one of my 2.0 conversion my car's rev's hunt. i was told to replace the plugs and leads.

i replaced the plugs and leads for standard ford ones, i think replaced my iscv with a fairly clean second hand one, i also replaced the tps while i as there

the other day my car would run,but as soon as the rev's dropped it would cut out,i replaced the lambda sensor and the car started idling oki replaced the maf while i was at it

i then disconnected the water temp sensor that sends signals to the ecu and the car idles ok and the rev's stopped hunting

i replaced the water temp sensor(new one) today and the car still does it Confused , when i disconnect it ,it seems to idle ok but smells very rich

the battery has been off since 10.30am this morning and was reconnected at 5.30pm, so the ecu was reset

i dont know what else to try or to check

i couldn't feel any vacum leaks, a few weeks ago the breather hose under the coil pack was replaced

but it does sound like a "tuff tuff" noise coming from the engine when i switch it off, but not a clue where its coming from as it only me, and i can hear it when i am by the drivers seat