P1507 Subaru -

Question

Have replaced Maf sensor, egr valve , back pressure transducer, new battery vacuum lines and it is now throwing the codes P0102 P0106 P0400 P1507 this on a 97 Subaru legacy outback 2.5 5 speed,

Answer 1

P1507 Idle control system malfunction (Fail Safe)

P0400 Exhaust gas recirculation flow malfunction

P0104 MAF circuit intermittent

P0102 MAF circuit low input

Check the SBF-2 main fuse, and the condition of the Main relay, If those are good then  P1507 is the main code , this can be cause by intake manifold loose which would cause a large intake vacuum leak,