I have a female connector that appears to run down to my exhaust and is shielded in braided wrap of some sort. This isnt actually connected up (the male connector goes towards the offside wing)
When I connect this up I get a light on my dash (whilst engine running) that is 3 along to the left of the check engine light (check engine isnt lit up)

You get the same light when you turn on ignition without firing the engine (this is if the connector is connected or not)

Does anyone know what this connector is for? is it the lambada sensor?
If this isnt connected could it cause my car to over/under fuel.
I have ran the diagnostics without the connector being connected and it doesnt throw up any error codes.
Any help would be appreciated

 

What model is it on?

I know i had to unplug a socket on the o/s inner wing when i fitted the decat downpipe.It wasnt a lambda sensor wire (as they are on the manifold pipes of my 95 wrx) When i checked it out it was a pre cat heat sensor wiring.This disconnected wont cause any fault codes and doesnt appear to make any difference.

 

Its on a MY93 wrx, I reckon your right about it being that as it definately goes under the manifest down below, ahh well something less to worry about then!!
cheers