Ive been hearing some clanking noises under my car for some time now so put her up on ramps. Wile I was checkin the trans mount (A4) i noticed a cluster of wires hangin down and they were tied into a small black box about half inch wide by two inchs long and has a red dot maybe a red light or somethin. Does anyone know what it is and what I should do with it?? Thanks

 

Looks like its comin from the main wiring harness above the trans then comes to a plugg then off the plugg is four wires that tie into this lil box and its all just hangin down. Not shure if it should be hooked up to somethin or what

 

Do you have headers? Sounds like O2 simulators.

 

Ah yes ive got headers the header 02s are there but diddnt check the rears ive never seen a simulator so that probly what it is. I had my rear 02 deleted when i had the egr and air done and the tunner said they were still there maybe thats what he was pickin up with is computer