I bought a 'P' reg impreza turbo about 4 months ago and the 'check engine' light came on at certain points but not at the same rev's and same gear everytime. I have had the engine changed, not because of this reason. I still have the same problem with the light coming on and there is a strange rasping noise when the light comes on too. I am planning on changing the knock sensor next week but dont know if that will sort it. It will be re-mapped aswell as it did have an EJ25 engine in before and now has the EJ20.

If anyone has any information please help. Thank you.

 

Leaking heads to headers/header to up-pipe/up-pipe to turbo/turbo to downpipe gasket?

Do a fault code check to see if any code/s come up...

 

you can read the codes by connection black connectors under the dash..

see my help pages

Simon

 

codes haver been read but it came up with no faults.

 

Well, that's good ...... But don't help you much re the direction to investigate, etc...