E46 Fanatics Forum banner

o2 Simulator circuit DIY

32K views 11 replies 8 participants last post by  wildcat293 
#1 ·
  • Like
Reactions: Al_Bundy
#5 · (Edited)
The only purpose of the post-cat o2 sensor is to detect whether the catalytic converter is functioning properly. This simulates the signal that the o2 sensor would send when the cat is functioning properly. (well simulates it close enough to fool the DME)

And yes, this is for simulation the post-cat o2 sensor only. Simulating a pre-cat o2 sensor would do all kinds of bad.
 
#7 ·
I do not recall what the power rating on the resistors was that I used, but the signal lines don't carry much power so 1/4 watt should be fine I would imagine. And yes I just used the old sensor's heater instead of simulating a heater circuit
 
#10 ·
Interesting, though sounds to me like they only really have an effect if the pre-cat sensor is starting to deteriorate.

Anyways I've not had an issue running without my own post-cat sensor. No gas mileage issues or anything else.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top