Does anyone know if i 2003 wrx lambda sensor is the same as 2002(bug) sensor?

 

possibly but the check the wires match and connector.

 

yes, if it is the 4 wire o2 sensor that fits into the manifold just before the up pipe.
2001 on will fit, wrx, sti, jdm,
these are very costly to replace as i just replaced mine.
£150 fom camskill was the cheapest i could find
over 200 from dealers

 

mshill - can I ask if you got the CEL on and the diagnostic code was P0031? If so that's what just happened to mine so I'm looking for the sensor now too! Is it a 4 wire one for the WRX then? (Mine is MY03). Does it just have a plug attached to it?