View Full Version : A4 1.8TQ AEB engine, disable rear oxygen sensor?

09-26-2010, 02:41 PM
Hi, i have been using a tapp 630cc ecu after my turbo upgrade. Bought the ecu used from another AEB A4. After installing this ecu i got an error when i scan with vag com. After alot of searching its saying that it has an error on heating on the rear oxygen sensor, and cant find any activety. Thats becouse my car didnt come with any rear oxygen sensor. Do this error cause any problems for me, or is it safe to drive this way? my fuel/air ratio is great. And is it any way to disable the rear oxygen sensor on the ecu? Or would there be any way to connect a rear oxygen sensor on my car that comes without this from the factory ? Thanks for all answers! And sorry for my bad english.

09-26-2010, 03:03 PM
You're sure you bought an AEB ecu? As far as I know none of the AEB ecu's have a 2nd sensor.

09-26-2010, 03:19 PM
You're sure you bought an AEB ecu? As far as I know none of the AEB ecu's have a 2nd sensor.

They do in North America. The 2nd one only tests to see if the cat is in the efficiency range its supposed to be.

09-26-2010, 03:28 PM
When i searched for aeb rear oxygen sensor i found several threads aboute it. I just thinks is not so common. Never seen a euro a4 have rear oxygen sensor.
So you are saying that i can just ignore the error and my car is fine to drive?

09-26-2010, 03:30 PM
its fine to drive that way. its just an annoying light from the CEL that is bothersome. get on the eurodyne website and find the closest maestro tuner to you. chances are he will flash the ecu you installed for very little to eliminate the need for the rear o2. It can't be done with vagcom.

09-26-2010, 03:46 PM
I dont have any light thats giving an error in the dash, only the vag com scan finds it. So no problem there. Is it possible for me to move the chip from the tapp ecu over to my original ecu and use it on that? My original ecu is chipped so the chip is not soldered on to the board. I dont know how the tapp ecu is made. But i do have soldering skills. But im not going to try this just becouse i find the error on my vag com scans. But if there would be any other problems for me.

09-26-2010, 03:58 PM
I also have an error on my evap, its leaking or something. Can this be the reason for the cruise control not working?

09-27-2010, 11:34 AM
Just to clear up the cruise controll issue, i fixed it with the resoldering of the cruise controll module. Now it works great!