May be not the right forum for this, don't shoot me I need urgent help for a friend.
Does anybody know what Select Monitor fault code “PO 420” means in new age Imprezas both WRX&STI?
Thanks in advance.
JIM

Jim

The "PO420" is the "Catalyst below efficiency threshold" warning in the new age WRX. Normally comes on when you decat the car unless you buy a fix box from ScoobySport or Pony Express.

Duncan ;)

Edited to add that, if I remember correctly, this warning is based on the efficiency of the downpipe cat and isn't normally triggered by changes to the uppipe or the 3rd cat.

[Edited by BugEyed - 11/13/2002 4:03:54 PM]

Jim

Removing the up pipe or downpipe cats will trigger this error code. It makes no effect on the running of the car and can be cured by fitting an electronic fix that modifies the signal from the rear O2 sensor.

Thanks guys, just found it on Ravensblade site.
Pete AFAIK you shell CEL fix device.
I'll ask my friend (he is mechanic) if he wants some; please tell me the price if possible.
Cheers
JIM

There is one for sale in "for sale forum" posted by NickAdams