When i bought my 51plate impreza sport (not the bugeye) the engine light was on & was told its been plugged in to computer & it was lambda sensor which was proved correct the other day!. i have changed the sensor with a decent bosch universal type, all was needed was to re-use the fitting off old one. took it for run , fine light stayed off then tonight the bloody light is back on??????
I put post on few days ago about the voltage output on it as mate has had same trouble with his 94 wrx & although when plugged in to check fault it comes up clear, it regulary comes on & off ????
Please can someone help us get to bottom of it as very annoying & tell us where we going wrong!

 

Can andybody out there help?
Have even tried resetting ecu but still came on some1 out there must have bit of an idea what i need to do to sort it out.

 

Could a knackered knock sensor be causing this problem?