high idle
 

Attachment 72339can anyone help,
just finished putting my engine back together and went for the start up but to no avail so ended up getting a new battery and the thing fired up straight away, however the revs were around 1800 and had an engine warning light on, so i checked it and it came up with P1507 - Powertrain, so i looked it up and it said Idle Control System Malfunction Fail Safe (SUBARU). next i got another throttle body and replaced it but to no avail it still does the same starts around 1800-2000 revs then settles down to around 1500revs.
ive checked and cleaned the earths on the manifold, cleaned the contacts for the idle control valve but i am stuck now, ive checked the vacuum pipes but im really not sure whats what when it comes to the pipes so anyone help would be appreciated fellas

Some kind of vacuum leak maybe? The whole intake system is under vacuum in idle and normal (off boost) conditions.